diff --git a/Cargo.lock b/Cargo.lock
index 61545ba..1e3da14 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -6894,6 +6894,7 @@ dependencies = [
  "unlucky-agent",
  "unlucky-cli",
  "unlucky-core",
+ "unlucky-presenter",
 ]
 
 [[package]]
@@ -6904,6 +6905,7 @@ dependencies = [
  "image",
  "unlucky-cli",
  "unlucky-design",
+ "unlucky-presenter",
 ]
 
 [[package]]
@@ -6940,6 +6942,15 @@ dependencies = [
 name = "unlucky-design"
 version = "0.1.0"
 
+[[package]]
+name = "unlucky-presenter"
+version = "0.1.0"
+dependencies = [
+ "serde",
+ "serde_json",
+ "unlucky-core",
+]
+
 [[package]]
 name = "unsafe-libyaml"
 version = "0.2.11"
diff --git a/Cargo.toml b/Cargo.toml
index 7562c83..1caed83 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,9 @@ resolver = "2"
 members = [
     "crates/core",
     "crates/agent",
+    # M85（D26）：UI 框架无关的宿主层。Slint 版（crates/app）与 iced 版（crates/app-iced）
+    # 共用它；Slint 退役后只剩 iced 依赖，本 crate 不受影响。
+    "crates/presenter",
     "crates/app",
     "crates/cli",
     "crates/design",
diff --git a/crates/app-iced/Cargo.toml b/crates/app-iced/Cargo.toml
index 8e60213..5df31dc 100644
--- a/crates/app-iced/Cargo.toml
+++ b/crates/app-iced/Cargo.toml
@@ -24,6 +24,11 @@ path = "src/lib.rs"
 # 令牌唯一真源（M61）：颜色/排版/形状/间距/图标几何全部只从这里取。
 unlucky-design = { path = "../design", version = "0.1" }
 
+# M85：UI 框架无关的宿主层（DTO / 状态 reducer / host）。**只登记依赖，本 mission 不接线**——
+# 页面用它的时机由后续 iced 页面 mission 决定（接线流程见 crates/presenter/src/lib.rs 的 crate 文档）。
+# 与 Slint 版共用同一套 host 与状态语义，这是 D26「重写只换渲染」的落点。
+unlucky-presenter = { path = "../presenter", version = "0.1" }
+
 # UI 框架（D26 锁定 iced 0.14）。**不得依赖 slint**。
 # 关掉默认 features 后必须显式给执行器（M60 踩坑 Q2：否则 `No futures executor has been enabled`），
 # 这里给 `thread-pool`（iced 自己的默认执行器，不额外引 tokio 运行时）。
diff --git a/crates/app/Cargo.toml b/crates/app/Cargo.toml
index 1fb2cde..a83e5ff 100644
--- a/crates/app/Cargo.toml
+++ b/crates/app/Cargo.toml
@@ -21,9 +21,18 @@ serde.workspace = true
 # host 层要读 core 设置/事件里的 JSON 值（serde_json 是 workspace 既有依赖）
 serde_json.workspace = true
 
+# M85：UI 框架无关的宿主层（DTO / 状态 reducer / host / 设置桥 / 偏好 / 路由 / 对话框 / 提示 /
+# 向导 / 假后端）。Slint 版与 iced 版共用这一层，所以 `crates/app` 只是它的**消费者**：
+# 本 crate 里剩下的 `crate::` 引用都换成了 `unlucky_presenter::`。
+#
+# presenter 的零 UI 依赖守门（原文与实测输出就在这里，放不进 present 的自家文档——自指）：
+#   grep -rn slint crates/presenter                 # 期望：无输出
+#   cargo tree -p unlucky-presenter --edges normal   # 期望：只有 serde/serde_json/unlucky-core
+unlucky-presenter = { path = "../presenter", version = "0.1" }
+
 # 边界（01c §5 / D3）：app 只经 DTO 消费 core/agent，**不 import 内部类型**。
-# P0 的 host 是 src/mock.rs 的假后端；这两个依赖在这里登记，是为了后续把真实 host
-# （core 的快照/事件流翻译成 src/dto 的类型）落位时不必再动 workspace 契约。
+# 迁移到 presenter 之后，app 侧只剩视图模型转换（`conv/ui.rs` 的 BgFill/强调色映射）与
+# 系统主题探测需要 core；业务装配（读盘/起进程/写设置）全部在 presenter 的 host 里。
 unlucky-core = { path = "../core", version = "0.1" }
 unlucky-agent = { path = "../agent", version = "0.1" }
 # M82：同一个二进制也带 CLI 子命令（`unlucky-launcher instances list` …）。
diff --git a/crates/app/src/bg_image.rs b/crates/app/src/bg_image.rs
index 0dca80e..a47004e 100644
--- a/crates/app/src/bg_image.rs
+++ b/crates/app/src/bg_image.rs
@@ -13,7 +13,7 @@
 
 use slint::{Image, Rgba8Pixel, SharedPixelBuffer};
 
-use crate::prefs::BgFill;
+use unlucky_presenter::prefs::BgFill;
 
 /// 模糊层目标宽度（像素）。越小越糊；96 在 1180px 宽窗口上 ≈ 24px 半径高斯的效果。
 const BLUR_WIDTH: u32 = 96;
diff --git a/crates/app/src/callbacks.rs b/crates/app/src/callbacks.rs
index d3ddcdd..eab031a 100644
--- a/crates/app/src/callbacks.rs
+++ b/crates/app/src/callbacks.rs
@@ -8,10 +8,10 @@ use std::rc::Weak;
 use slint::ComponentHandle;
 
 use crate::conv;
-use crate::dto::AppCommand;
-use crate::router::Route;
-use crate::toast::ToastKind;
 use crate::ui_bind::Inner;
+use unlucky_presenter::dto::AppCommand;
+use unlucky_presenter::router::Route;
+use unlucky_presenter::toast::ToastKind;
 
 /// 接全部回调；闭包持弱引用，避免 `MainWindow` 与闭包互相持有导致窗口永不释放。
 pub(crate) fn wire(weak: Weak<Inner>) {
@@ -181,7 +181,7 @@ fn wire_instances(ui: &crate::MainWindow, weak: &Weak<Inner>) {
         ui.on_new_instance(move || {
             let Some(this) = weak.upgrade() else { return };
             // G5：打开向导（版本 → 加载器 → 名字 → 确认 → 安装进度）
-            this.state.borrow_mut().wizard = crate::wizard::WizardState::open();
+            this.state.borrow_mut().wizard = unlucky_presenter::wizard::WizardState::open();
             this.sync();
         });
     }
diff --git a/crates/app/src/callbacks_pages.rs b/crates/app/src/callbacks_pages.rs
index cdb89da..19623f9 100644
--- a/crates/app/src/callbacks_pages.rs
+++ b/crates/app/src/callbacks_pages.rs
@@ -8,8 +8,8 @@ use std::rc::Weak;
 use slint::ComponentHandle;
 
 use crate::conv;
-use crate::dto::{AppCommand, CreateRequest, LoaderKind};
 use crate::ui_bind::Inner;
+use unlucky_presenter::dto::{AppCommand, CreateRequest, LoaderKind};
 
 /// 接全部页面状态回调。
 pub(crate) fn wire_pages(weak: Weak<Inner>) {
@@ -137,7 +137,7 @@ pub(crate) fn wire_pages(weak: Weak<Inner>) {
         let weak = weak.clone();
         page.on_wizard_open(move || {
             let Some(this) = weak.upgrade() else { return };
-            this.state.borrow_mut().wizard = crate::wizard::WizardState::open();
+            this.state.borrow_mut().wizard = unlucky_presenter::wizard::WizardState::open();
             this.sync();
         });
     }
diff --git a/crates/app/src/conv/agent.rs b/crates/app/src/conv/agent.rs
index bb1ed4a..9e32255 100644
--- a/crates/app/src/conv/agent.rs
+++ b/crates/app/src/conv/agent.rs
@@ -1,10 +1,10 @@
 //! AI 页与覆盖层：会话消息、对话框（一次一条）、Toast。
 
-use crate::dialogs as dlg;
-use crate::dto::ChatRole as DtoChatRole;
-use crate::state::AppState;
-use crate::toast as toast_mod;
 use crate::{ChatRole, DialogKind, UiChatMessage, UiDialog, UiToast};
+use unlucky_presenter::dialogs as dlg;
+use unlucky_presenter::dto::ChatRole as DtoChatRole;
+use unlucky_presenter::state::AppState;
+use unlucky_presenter::toast as toast_mod;
 
 /// AI 会话消息。
 pub fn chat(state: &AppState) -> Vec<UiChatMessage> {
diff --git a/crates/app/src/conv/instances.rs b/crates/app/src/conv/instances.rs
index 11ce32a..ddf60fb 100644
--- a/crates/app/src/conv/instances.rs
+++ b/crates/app/src/conv/instances.rs
@@ -2,9 +2,9 @@
 
 use slint::Color;
 
-use crate::dto::{self, InstanceRuntime};
-use crate::state::{AppState, TileCell};
 use crate::{LoaderKind, RuntimePhase, UiTile};
+use unlucky_presenter::dto::{self, InstanceRuntime};
+use unlucky_presenter::state::{AppState, TileCell};
 
 /// 头像/图标占位的底色池（Metro 强调色系，按 id 哈希稳定取色）。
 const HUES: [u32; 8] = [
diff --git a/crates/app/src/conv/logs.rs b/crates/app/src/conv/logs.rs
index ba72410..b678621 100644
--- a/crates/app/src/conv/logs.rs
+++ b/crates/app/src/conv/logs.rs
@@ -1,8 +1,8 @@
 //! 日志页：会话列表、日志行、D8 诊断卡片。
 
-use crate::dto::{LogLevel as DtoLogLevel, LogOutcome as DtoLogOutcome};
-use crate::state::AppState;
 use crate::{LogLevel, LogOutcome, UiDiagnosis, UiLogLine, UiLogSession};
+use unlucky_presenter::dto::{LogLevel as DtoLogLevel, LogOutcome as DtoLogOutcome};
+use unlucky_presenter::state::AppState;
 
 /// 日志会话列表。
 pub fn log_sessions(state: &AppState) -> Vec<UiLogSession> {
diff --git a/crates/app/src/conv/pages.rs b/crates/app/src/conv/pages.rs
index 4c1a4df..b375c1e 100644
--- a/crates/app/src/conv/pages.rs
+++ b/crates/app/src/conv/pages.rs
@@ -5,17 +5,17 @@
 
 use slint::{ModelRc, SharedString, VecModel};
 
-use crate::dto::{
-    AccountKind as DtoAccountKind, DeviceLoginPhase, InstallStage as DtoInstallStage,
-    JavaChainOutcome, NoticeLevel, SettingControl, VersionKind as DtoVersionKind,
-};
-use crate::state::AppState;
-use crate::wizard::WizardStep;
 use crate::{
     AccountKind, InstallStage, JavaStepOutcome, NoticeKind, SettingControl as UiControl, UiAccount,
     UiDeviceCode, UiInstallProgress, UiJavaRuntime, UiJavaStep, UiJavaVendor, UiNotice,
     UiSettingGroup, UiSettingRow, UiVersion, UiWizard,
 };
+use unlucky_presenter::dto::{
+    AccountKind as DtoAccountKind, DeviceLoginPhase, InstallStage as DtoInstallStage,
+    JavaChainOutcome, NoticeLevel, SettingControl, VersionKind as DtoVersionKind,
+};
+use unlucky_presenter::state::AppState;
+use unlucky_presenter::wizard::WizardStep;
 
 fn strings(items: &[String]) -> ModelRc<SharedString> {
     ModelRc::new(VecModel::from(
@@ -162,8 +162,8 @@ pub fn install(state: &AppState) -> UiInstallProgress {
         bytes_label: if progress.bytes_total > 0 {
             format!(
                 "{}/{}",
-                crate::dto::human_bytes(progress.bytes_done),
-                crate::dto::human_bytes(progress.bytes_total)
+                unlucky_presenter::dto::human_bytes(progress.bytes_done),
+                unlucky_presenter::dto::human_bytes(progress.bytes_total)
             )
         } else {
             String::new()
@@ -236,7 +236,7 @@ pub fn wizard(state: &AppState) -> UiWizard {
     let step = wizard.step;
     let can_next = match step {
         WizardStep::Version => !wizard.version.trim().is_empty(),
-        WizardStep::Name => crate::wizard::validate_name(&wizard.name).is_ok(),
+        WizardStep::Name => unlucky_presenter::wizard::validate_name(&wizard.name).is_ok(),
         WizardStep::Loader | WizardStep::Confirm => true,
         WizardStep::Progress => false,
     };
@@ -248,7 +248,7 @@ pub fn wizard(state: &AppState) -> UiWizard {
         step_total: 5,
         version: wizard.version.as_str().into(),
         loader: loader_index(wizard.loader),
-        loader_label: if wizard.loader == crate::dto::LoaderKind::Vanilla {
+        loader_label: if wizard.loader == unlucky_presenter::dto::LoaderKind::Vanilla {
             "原版".to_string()
         } else {
             format!("{} {}", wizard.loader.label(), wizard.loader_version.trim())
@@ -265,14 +265,15 @@ pub fn wizard(state: &AppState) -> UiWizard {
 }
 
 /// 加载器在向导里的单选序号（与 `wizard.slint` 的 LoaderChoice 顺序一致）。
-pub fn loader_index(loader: crate::dto::LoaderKind) -> i32 {
+pub fn loader_index(loader: unlucky_presenter::dto::LoaderKind) -> i32 {
     match loader {
-        crate::dto::LoaderKind::Vanilla => 0,
-        crate::dto::LoaderKind::Fabric => 1,
-        crate::dto::LoaderKind::Quilt => 2,
-        crate::dto::LoaderKind::Forge => 3,
-        crate::dto::LoaderKind::NeoForge => 4,
-        crate::dto::LoaderKind::OptiFine | crate::dto::LoaderKind::LiteLoader => 0,
+        unlucky_presenter::dto::LoaderKind::Vanilla => 0,
+        unlucky_presenter::dto::LoaderKind::Fabric => 1,
+        unlucky_presenter::dto::LoaderKind::Quilt => 2,
+        unlucky_presenter::dto::LoaderKind::Forge => 3,
+        unlucky_presenter::dto::LoaderKind::NeoForge => 4,
+        unlucky_presenter::dto::LoaderKind::OptiFine
+        | unlucky_presenter::dto::LoaderKind::LiteLoader => 0,
     }
 }
 
diff --git a/crates/app/src/conv/pages_tests.rs b/crates/app/src/conv/pages_tests.rs
index cd7f23b..e6e6d09 100644
--- a/crates/app/src/conv/pages_tests.rs
+++ b/crates/app/src/conv/pages_tests.rs
@@ -1,12 +1,12 @@
 //! conv/pages.rs 的单测（拆文件守 400 行上限）。
 
 use super::*;
-use crate::dto::{
+use slint::Model;
+use unlucky_presenter::dto::{
     AccountView, DeviceLoginView, InstallProgressView, JavaPageView, JavaVendorView, NoticeView,
     SettingGroupView, SettingRowView, VersionSummary,
 };
-use crate::wizard::WizardState;
-use slint::Model;
+use unlucky_presenter::wizard::WizardState;
 
 #[test]
 fn accounts_and_device_login_render() {
@@ -90,7 +90,7 @@ fn java_chain_and_vendors_map_outcomes() {
             sources: vec!["BMCLAPI".to_string(), "GitHub".to_string()],
             installed: true,
         }],
-        chain: vec![crate::dto::JavaChainStep {
+        chain: vec![unlucky_presenter::dto::JavaChainStep {
             vendor: "temurin".to_string(),
             outcome: JavaChainOutcome::Hit,
             detail: "21".to_string(),
@@ -161,7 +161,7 @@ fn wizard_versions_skip_ancient_ones() {
         },
         VersionSummary {
             id: "rd-132211".to_string(),
-            kind: DtoVersionKind::Ancient(crate::dto::AncientKind::Classic),
+            kind: DtoVersionKind::Ancient(unlucky_presenter::dto::AncientKind::Classic),
             released: "2009-05-13".to_string(),
             installed: false,
         },
diff --git a/crates/app/src/conv/ui.rs b/crates/app/src/conv/ui.rs
index 22c6d20..d9fb094 100644
--- a/crates/app/src/conv/ui.rs
+++ b/crates/app/src/conv/ui.rs
@@ -1,9 +1,9 @@
 //! UI 偏好/路由枚举的双向映射（Slint 枚举 ↔ 状态层枚举）。
 
-use crate::dto::{self, VersionCategory};
-use crate::prefs;
-use crate::router;
 use crate::{BgFillKind, DownloadCategory, InstanceView, RouteKind, ThemeMode, TileSize};
+use unlucky_presenter::dto::{self, VersionCategory};
+use unlucky_presenter::prefs;
+use unlucky_presenter::router;
 
 /// 路由 → 导航高亮/页面选择。
 pub fn route(route: &router::Route) -> RouteKind {
diff --git a/crates/app/src/conv/versions.rs b/crates/app/src/conv/versions.rs
index 3459dd4..7105742 100644
--- a/crates/app/src/conv/versions.rs
+++ b/crates/app/src/conv/versions.rs
@@ -1,8 +1,10 @@
 //! 版本列表与下载分类映射（下载页）。
 
-use crate::dto::{AncientKind, VersionCategory, VersionKind as DtoVersionKind, VersionSummary};
-use crate::state::AppState;
 use crate::{UiVersion, VersionKind};
+use unlucky_presenter::dto::{
+    AncientKind, VersionCategory, VersionKind as DtoVersionKind, VersionSummary,
+};
+use unlucky_presenter::state::AppState;
 
 /// 分类侧栏 → 该分类下的版本（远古版按子类细分）。
 pub fn in_category(category: VersionCategory, kind: DtoVersionKind) -> bool {
@@ -58,8 +60,8 @@ fn version_kind(kind: DtoVersionKind) -> VersionKind {
 #[cfg(test)]
 mod tests {
     use super::versions;
-    use crate::dto::{VersionKind, VersionSummary};
-    use crate::state::AppState;
+    use unlucky_presenter::dto::{VersionKind, VersionSummary};
+    use unlucky_presenter::state::AppState;
 
     fn state_with_versions() -> AppState {
         let mut state = AppState::new();
diff --git a/crates/app/src/main.rs b/crates/app/src/main.rs
index 03789a8..13e23d9 100644
--- a/crates/app/src/main.rs
+++ b/crates/app/src/main.rs
@@ -2,7 +2,7 @@
 //!
 //! 边界（决策 D3 / D16）：本 crate 是**唯一**允许依赖 UI 框架的 crate；
 //! 它只经「快照 + 事件流 + 注入的显示服务」消费 core/agent，不直接触碰其内部类型
-//! （P0 的 host 是 `mock` 假后端，`crate::dto` 是唯一跨界类型集合）。
+//! （P0 的 host 是 `mock` 假后端，`unlucky_presenter::dto` 是唯一跨界类型集合）。
 //!
 //! 渲染策略（`DevDocs/PlanDoc/01c-native-gui-options.md` §6）：
 //! GL 优先（femtovg），启动参数 `--software-renderer` 或 Win7 老机探测失败时切 CPU 软渲染。
@@ -10,7 +10,7 @@
 //! 主题与外观（D17 / 09 §101-113）：
 //! - 主题三态 `appearance.theme_mode ∈ {auto, light, dark}`（出厂 auto）；
 //! - 「外观（高级）」四件（背景图 / 面板半透明度 / 玻璃拟态 / 强调色）出厂全关；
-//! - 全部走 `core::setting` 的 schema（`crate::settings_bridge`），AI 可写并且**热切**
+//! - 全部走 `core::setting` 的 schema（`unlucky_presenter::settings_bridge`），AI 可写并且**热切**
 //!   （tick 里 1s 一次 mtime 比对）；系统主题由 `core::platform::theme_probe` 对齐 + 兜底轮询。
 //!
 //! 一个二进制两种用法（M82）：`unlucky-launcher` 不带子命令时起 GUI；带子命令
@@ -41,27 +41,15 @@
 use std::process::ExitCode;
 
 mod appearance_bind;
-mod backend;
 mod bg_image;
 mod callbacks;
 mod callbacks_pages;
 mod conv;
-mod dialogs;
-mod dto;
-mod host;
-mod mock;
-mod mock_data;
 mod page_sync;
 mod png;
-mod prefs;
-mod router;
 mod screenshot;
-mod settings_bridge;
-mod state;
 mod theme_runtime;
-mod toast;
 mod ui_bind;
-mod wizard;
 
 slint::include_modules!();
 
diff --git a/crates/app/src/page_sync.rs b/crates/app/src/page_sync.rs
index 3ed06ea..578e0c8 100644
--- a/crates/app/src/page_sync.rs
+++ b/crates/app/src/page_sync.rs
@@ -4,10 +4,10 @@
 //! （`ui_bind::Inner::sync`）。分文件而不是砍内容：这些字段每一行都对应一个页面元素。
 
 use crate::conv;
-use crate::state::AppState;
 use crate::ui_bind::model;
 use crate::{MainWindow, PageState};
 use slint::ComponentHandle;
+use unlucky_presenter::state::AppState;
 
 /// 把页面状态灌进 `PageState`。
 pub(crate) fn apply(ui: &MainWindow, state: &AppState) {
diff --git a/crates/app/src/screenshot.rs b/crates/app/src/screenshot.rs
index 50d74a4..7c761f0 100644
--- a/crates/app/src/screenshot.rs
+++ b/crates/app/src/screenshot.rs
@@ -9,9 +9,9 @@
 
 use std::path::PathBuf;
 
-use crate::backend::AppOptions;
-use crate::dto::AppCommand;
 use crate::ui_bind::AppUi;
+use unlucky_presenter::backend::AppOptions;
+use unlucky_presenter::dto::AppCommand;
 
 /// 一次截图请求。
 #[derive(Debug, Clone, Default)]
@@ -121,8 +121,8 @@ pub fn capture(app: &AppUi, options: &ShotOptions) -> Result<(), slint::Platform
 /// 截图通道的安装指令：缺省原版，给了 `--screenshot-loader` 就走向导同一条路
 /// （`CreateInstance`），因此 Forge/NeoForge 的中间态也能取图。
 fn install_command(version: &str, loader: Option<&str>) -> AppCommand {
-    match loader.map(crate::dto::LoaderKind::parse) {
-        Some(Some(kind)) => AppCommand::CreateInstance(crate::dto::CreateRequest {
+    match loader.map(unlucky_presenter::dto::LoaderKind::parse) {
+        Some(Some(kind)) => AppCommand::CreateInstance(unlucky_presenter::dto::CreateRequest {
             version: version.to_string(),
             loader: kind,
             loader_version: String::new(),
diff --git a/crates/app/src/theme_runtime.rs b/crates/app/src/theme_runtime.rs
index 851e612..b8fccab 100644
--- a/crates/app/src/theme_runtime.rs
+++ b/crates/app/src/theme_runtime.rs
@@ -7,15 +7,16 @@ use slint::ComponentHandle;
 
 use crate::bg_image::{self, BackgroundLayers};
 use crate::conv;
-use crate::prefs::{AppearancePrefs, BgFill, ThemeMode};
-use crate::toast::ToastKind;
-use crate::ui_bind::{
-    BackgroundKey, Inner, CONFIG_POLL_TICKS, SYSTEM_THEME_POLL_TICKS, TILE_REGENERATE_STEP,
+use crate::ui_bind::Inner;
+use unlucky_presenter::prefs::{AppearancePrefs, BgFill, ThemeMode};
+use unlucky_presenter::theme::{
+    config_poll_due, system_theme_poll_due, system_theme_value, BackgroundKey,
 };
+use unlucky_presenter::toast::ToastKind;
 
 impl Inner {
     pub(crate) fn poll_settings(&self) {
-        if !self.ticks.get().is_multiple_of(CONFIG_POLL_TICKS) {
+        if !config_poll_due(self.ticks.get()) {
             return;
         }
         let Some((appearance, theme)) = self.bridge.borrow_mut().reload_if_changed() else {
@@ -35,17 +36,17 @@ impl Inner {
     pub(crate) fn poll_system_theme(&self) {
         let auto = matches!(self.state.borrow().prefs.theme, ThemeMode::Auto);
         let backend_known = self.ui.get_system_theme_known();
-        let due = !self.system_theme_probed.get()
-            || (auto && !backend_known && self.ticks.get().is_multiple_of(SYSTEM_THEME_POLL_TICKS));
+        let due = system_theme_poll_due(
+            self.system_theme_probed.get(),
+            auto,
+            backend_known,
+            self.ticks.get(),
+        );
         if !due {
             return;
         }
         self.system_theme_probed.set(true);
-        let value = match unlucky_core::platform::theme_probe::probe() {
-            unlucky_core::platform::theme_probe::SystemTheme::Light => 1,
-            unlucky_core::platform::theme_probe::SystemTheme::Dark => 2,
-            unlucky_core::platform::theme_probe::SystemTheme::Unknown => 0,
-        };
+        let value = system_theme_value();
         if self.ui.get_system_theme() != value {
             self.ui.set_system_theme(value);
         }
@@ -124,16 +125,15 @@ impl Inner {
         }
     }
 
-    /// tile 画布的窗口尺寸（量化到 [`TILE_REGENERATE_STEP`]，避免拖动窗口时反复重算）。
+    /// tile 画布的窗口尺寸（量化到 `TILE_REGENERATE_STEP`，避免拖动窗口时反复重算）。
+    ///
+    /// 判据在 [`unlucky_presenter::theme::tile_viewport`]（两侧 UI 共用一份）；这里只负责
+    /// 提供窗口物理尺寸。
     fn tile_viewport(&self, fill: BgFill) -> (u32, u32) {
         if fill != BgFill::Tile {
             return (0, 0);
         }
-        let (width, height) = self.window_physical_size();
-        (
-            width / TILE_REGENERATE_STEP * TILE_REGENERATE_STEP,
-            height / TILE_REGENERATE_STEP * TILE_REGENERATE_STEP,
-        )
+        unlucky_presenter::theme::tile_viewport(fill, self.window_physical_size())
     }
 
     /// 窗口物理像素尺寸（取不到时 (0, 0)，tile 退化为单块）。
diff --git a/crates/app/src/ui_bind.rs b/crates/app/src/ui_bind.rs
index b978ec2..6b5d07e 100644
--- a/crates/app/src/ui_bind.rs
+++ b/crates/app/src/ui_bind.rs
@@ -14,27 +14,18 @@ use std::time::Duration;
 
 use slint::{ComponentHandle, ModelRc, VecModel};
 
-use crate::backend::{build_backend, config_path, AppOptions};
 use crate::bg_image::BackgroundLayers;
 use crate::conv;
-use crate::dto::{AppCommand, Backend};
-use crate::prefs::BgFill;
-use crate::settings_bridge::SettingsBridge;
-use crate::state::AppState;
 use crate::{MainWindow, PageState, SettingSection};
+use unlucky_presenter::backend::{build_backend, config_path, AppOptions};
+use unlucky_presenter::dto::{AppCommand, Backend};
+use unlucky_presenter::settings_bridge::SettingsBridge;
+use unlucky_presenter::state::AppState;
+use unlucky_presenter::theme::BackgroundKey;
 
 /// 定时器节拍：33ms ≈ 30fps（磁贴进度环 / 流式文本 / Toast TTL 的刷新下限）。
 const TICK_MS: u64 = 33;
 
-/// 配置热切轮询间隔（拍数）：约 1s 一次 `mtime` 比对，AI/CLI 改完下一拍即生效。
-pub(crate) const CONFIG_POLL_TICKS: u64 = 30;
-
-/// 系统主题兜底轮询间隔（拍数）：只在 `auto` 且后端不认识系统主题时启动（约 3s）。
-pub(crate) const SYSTEM_THEME_POLL_TICKS: u64 = 90;
-
-/// tile 模式重建画布的窗口尺寸粒度（像素）：避免拖动窗口时反复重算平铺画布。
-pub(crate) const TILE_REGENERATE_STEP: u32 = 128;
-
 /// 应用外壳：持有窗口、状态与后端，把三者缝在一起。
 pub struct AppUi {
     inner: Rc<Inner>,
@@ -57,15 +48,6 @@ pub(crate) struct Inner {
     pub(crate) system_theme_probed: Cell<bool>,
 }
 
-/// 背景图加工输入（值相同就不重新解码）。
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub(crate) struct BackgroundKey {
-    pub(crate) path: String,
-    pub(crate) fill: BgFill,
-    /// tile 用的窗口尺寸（按 [`TILE_REGENERATE_STEP`] 量化；cover/contain 恒为 (0, 0)）
-    pub(crate) viewport: (u32, u32),
-}
-
 impl AppUi {
     /// 建状态 + 真实后端、读配置、接全部回调、灌初始事件并做第一次同步。
     pub fn new(ui: MainWindow) -> Self {
@@ -136,7 +118,7 @@ impl AppUi {
         self.inner
             .state
             .borrow_mut()
-            .navigate(crate::router::Route::Settings);
+            .navigate(unlucky_presenter::router::Route::Settings);
         self.inner.sync();
         self.inner
             .ui
@@ -147,11 +129,11 @@ impl AppUi {
     /// 直接跳到一个页面（截图验收用：每页一张）。
     pub fn open_page(&self, page: &str) {
         let route = match page {
-            "download" | "java" => crate::router::Route::Download,
-            "logs" => crate::router::Route::Logs,
-            "settings" | "account" | "appearance" => crate::router::Route::Settings,
-            "agent" => crate::router::Route::Agent,
-            _ => crate::router::Route::Instances,
+            "download" | "java" => unlucky_presenter::router::Route::Download,
+            "logs" => unlucky_presenter::router::Route::Logs,
+            "settings" | "account" | "appearance" => unlucky_presenter::router::Route::Settings,
+            "agent" => unlucky_presenter::router::Route::Agent,
+            _ => unlucky_presenter::router::Route::Instances,
         };
         {
             let mut state = self.inner.state.borrow_mut();
@@ -184,7 +166,7 @@ impl AppUi {
 
     /// 打开新建实例向导（截图验收用）。
     pub fn open_wizard(&self) {
-        self.inner.state.borrow_mut().wizard = crate::wizard::WizardState::open();
+        self.inner.state.borrow_mut().wizard = unlucky_presenter::wizard::WizardState::open();
         self.inner.sync();
         slint::platform::update_timers_and_animations();
     }
diff --git a/crates/presenter/Cargo.toml b/crates/presenter/Cargo.toml
new file mode 100644
index 0000000..1bd0061
--- /dev/null
+++ b/crates/presenter/Cargo.toml
@@ -0,0 +1,28 @@
+[package]
+name = "unlucky-presenter"
+description = "Unlucky-Launcher 的 UI 框架无关宿主层：DTO / 状态 reducer / host 业务装配，Slint 版与 iced 版共用"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+authors.workspace = true
+repository.workspace = true
+rust-version.workspace = true
+publish.workspace = true
+
+# 零 UI 框架依赖是硬约束（M85 / D26）：本 crate 是 Slint 版（`crates/app`）与 iced 版
+# （`crates/app-iced`）共用的宿主层，任何时候都不得出现 Slint / iced / winit / gtk / egui 等
+# UI 或渲染框架，也不得出现「把窗口属性灌进去」这种绑定代码。
+# 证据命令写在 `crates/app/Cargo.toml` 的注释里（那个文件允许出现框架名，本 crate 的守门
+# 命令本身在自家 grep 范围内会把自己抓出来，所以那两条命令刻意不放在这里）。
+[dependencies]
+# 跨边界 DTO 必须可序列化（AGENTS §6）：事件与快照是 IPC 契约，序列化能力由 derive 钉住。
+serde.workspace = true
+# host 层要读 core 设置/事件里的 JSON 值。
+serde_json.workspace = true
+
+# 边界（01c §5 / D3）：presenter 只经 DTO 消费 core，**不 import core 的领域类型到 DTO 里**。
+# host 是 core 的快照/事件流与本 crate DTO 之间的唯一翻译层，所以它需要 core。
+unlucky-core = { path = "../core", version = "0.1" }
+
+[lints]
+workspace = true
diff --git a/crates/app/src/backend.rs b/crates/presenter/src/backend.rs
similarity index 90%
rename from crates/app/src/backend.rs
rename to crates/presenter/src/backend.rs
index 224b786..1669aec 100644
--- a/crates/app/src/backend.rs
+++ b/crates/presenter/src/backend.rs
@@ -17,12 +17,12 @@ pub struct AppOptions {
 }
 
 /// `<root>/.ULL/config/launcher.json`（与 `SettingsBridge::open` 同落点）。
-pub(crate) fn config_path(root: &Path) -> PathBuf {
+pub fn config_path(root: &Path) -> PathBuf {
     root.join(".ULL").join("config").join("launcher.json")
 }
 
 /// 选后端：真实 host 优先；数据根解析不出来或显式 `--mock` 时退回假后端。
-pub(crate) fn build_backend(options: &AppOptions) -> Box<dyn Backend> {
+pub fn build_backend(options: &AppOptions) -> Box<dyn Backend> {
     if options.mock {
         return Box::new(MockBackend::new());
     }
diff --git a/crates/app/src/dialogs.rs b/crates/presenter/src/dialogs.rs
similarity index 100%
rename from crates/app/src/dialogs.rs
rename to crates/presenter/src/dialogs.rs
diff --git a/crates/app/src/dto/accounts.rs b/crates/presenter/src/dto/accounts.rs
similarity index 100%
rename from crates/app/src/dto/accounts.rs
rename to crates/presenter/src/dto/accounts.rs
diff --git a/crates/app/src/dto/agent.rs b/crates/presenter/src/dto/agent.rs
similarity index 100%
rename from crates/app/src/dto/agent.rs
rename to crates/presenter/src/dto/agent.rs
diff --git a/crates/app/src/dto/events.rs b/crates/presenter/src/dto/events.rs
similarity index 100%
rename from crates/app/src/dto/events.rs
rename to crates/presenter/src/dto/events.rs
diff --git a/crates/app/src/dto/install.rs b/crates/presenter/src/dto/install.rs
similarity index 100%
rename from crates/app/src/dto/install.rs
rename to crates/presenter/src/dto/install.rs
diff --git a/crates/app/src/dto/instances.rs b/crates/presenter/src/dto/instances.rs
similarity index 100%
rename from crates/app/src/dto/instances.rs
rename to crates/presenter/src/dto/instances.rs
diff --git a/crates/app/src/dto/java.rs b/crates/presenter/src/dto/java.rs
similarity index 100%
rename from crates/app/src/dto/java.rs
rename to crates/presenter/src/dto/java.rs
diff --git a/crates/app/src/dto/logs.rs b/crates/presenter/src/dto/logs.rs
similarity index 100%
rename from crates/app/src/dto/logs.rs
rename to crates/presenter/src/dto/logs.rs
diff --git a/crates/app/src/dto/mod.rs b/crates/presenter/src/dto/mod.rs
similarity index 84%
rename from crates/app/src/dto/mod.rs
rename to crates/presenter/src/dto/mod.rs
index 38c2cf0..4bd5e6a 100644
--- a/crates/app/src/dto/mod.rs
+++ b/crates/presenter/src/dto/mod.rs
@@ -1,6 +1,6 @@
-//! app ↔ core/agent 的 IPC 边界（01c §5 纪律）。
+//! presenter ↔ core/agent 的 IPC 边界（01c §5 纪律）。
 //!
-//! 这里只允许出现「扁平 DTO / 事件 / 指令」：`crates/app` 任何模块都不得 `use unlucky_core::*`
+//! 这里只允许出现「扁平 DTO / 事件 / 指令」：本 crate 的 DTO 里不得出现 `unlucky_core::*`
 //! 或 `use unlucky_agent::*` 的内部类型。core/agent 侧的 host 层负责把自身类型翻译成本模块的类型，
 //! 反向的 [`AppCommand`] 也一样。P0 阶段由 [`crate::mock`] 的假后端实现 [`Backend`] 驱动骨架，
 //! P3 起由 [`crate::host`] 的真实后端驱动全部页面。
@@ -8,7 +8,8 @@
 //! 结构：**按领域拆子模块**（instances / versions / logs / agent / accounts / java /
 //! settings / install / notices / events），全量 `pub use` 出去，调用方依旧写
 //! `crate::dto::InstanceSummary` 这类路径。
-//! 契约说明（字段口径、事件顺序、错误语义）见 `DevDocs/SubAgentsTalk/app-DTO通道约定.md`。
+//! 契约说明（字段口径、事件顺序、错误语义）见 `DevDocs/SubAgentsTalk/app-DTO通道约定.md`；
+//! UI 侧的唯一入口与 iced 接线用法见 crate 文档（`src/lib.rs`）。
 //!
 //! 全部跨界类型 `Serialize + Deserialize`（AGENTS §6）：事件与快照是 IPC 契约，
 //! 序列化能力由 derive 钉住，`dto` 的单测做 round-trip 断言。
diff --git a/crates/app/src/dto/notices.rs b/crates/presenter/src/dto/notices.rs
similarity index 100%
rename from crates/app/src/dto/notices.rs
rename to crates/presenter/src/dto/notices.rs
diff --git a/crates/app/src/dto/settings.rs b/crates/presenter/src/dto/settings.rs
similarity index 100%
rename from crates/app/src/dto/settings.rs
rename to crates/presenter/src/dto/settings.rs
diff --git a/crates/app/src/dto/versions.rs b/crates/presenter/src/dto/versions.rs
similarity index 100%
rename from crates/app/src/dto/versions.rs
rename to crates/presenter/src/dto/versions.rs
diff --git a/crates/app/src/host/accounts.rs b/crates/presenter/src/host/accounts.rs
similarity index 100%
rename from crates/app/src/host/accounts.rs
rename to crates/presenter/src/host/accounts.rs
diff --git a/crates/app/src/host/dispatch.rs b/crates/presenter/src/host/dispatch.rs
similarity index 100%
rename from crates/app/src/host/dispatch.rs
rename to crates/presenter/src/host/dispatch.rs
diff --git a/crates/app/src/host/engine.rs b/crates/presenter/src/host/engine.rs
similarity index 100%
rename from crates/app/src/host/engine.rs
rename to crates/presenter/src/host/engine.rs
diff --git a/crates/app/src/host/env.rs b/crates/presenter/src/host/env.rs
similarity index 100%
rename from crates/app/src/host/env.rs
rename to crates/presenter/src/host/env.rs
diff --git a/crates/app/src/host/game.rs b/crates/presenter/src/host/game.rs
similarity index 100%
rename from crates/app/src/host/game.rs
rename to crates/presenter/src/host/game.rs
diff --git a/crates/app/src/host/handle.rs b/crates/presenter/src/host/handle.rs
similarity index 100%
rename from crates/app/src/host/handle.rs
rename to crates/presenter/src/host/handle.rs
diff --git a/crates/app/src/host/identity.rs b/crates/presenter/src/host/identity.rs
similarity index 100%
rename from crates/app/src/host/identity.rs
rename to crates/presenter/src/host/identity.rs
diff --git a/crates/app/src/host/install.rs b/crates/presenter/src/host/install.rs
similarity index 100%
rename from crates/app/src/host/install.rs
rename to crates/presenter/src/host/install.rs
diff --git a/crates/app/src/host/install_journal.rs b/crates/presenter/src/host/install_journal.rs
similarity index 100%
rename from crates/app/src/host/install_journal.rs
rename to crates/presenter/src/host/install_journal.rs
diff --git a/crates/app/src/host/install_processors.rs b/crates/presenter/src/host/install_processors.rs
similarity index 100%
rename from crates/app/src/host/install_processors.rs
rename to crates/presenter/src/host/install_processors.rs
diff --git a/crates/app/src/host/install_processors_fixture.rs b/crates/presenter/src/host/install_processors_fixture.rs
similarity index 100%
rename from crates/app/src/host/install_processors_fixture.rs
rename to crates/presenter/src/host/install_processors_fixture.rs
diff --git a/crates/app/src/host/install_processors_tests.rs b/crates/presenter/src/host/install_processors_tests.rs
similarity index 100%
rename from crates/app/src/host/install_processors_tests.rs
rename to crates/presenter/src/host/install_processors_tests.rs
diff --git a/crates/app/src/host/install_tests.rs b/crates/presenter/src/host/install_tests.rs
similarity index 100%
rename from crates/app/src/host/install_tests.rs
rename to crates/presenter/src/host/install_tests.rs
diff --git a/crates/app/src/host/java.rs b/crates/presenter/src/host/java.rs
similarity index 100%
rename from crates/app/src/host/java.rs
rename to crates/presenter/src/host/java.rs
diff --git a/crates/app/src/host/job.rs b/crates/presenter/src/host/job.rs
similarity index 100%
rename from crates/app/src/host/job.rs
rename to crates/presenter/src/host/job.rs
diff --git a/crates/app/src/host/launch.rs b/crates/presenter/src/host/launch.rs
similarity index 100%
rename from crates/app/src/host/launch.rs
rename to crates/presenter/src/host/launch.rs
diff --git a/crates/app/src/host/launch_state_tests.rs b/crates/presenter/src/host/launch_state_tests.rs
similarity index 100%
rename from crates/app/src/host/launch_state_tests.rs
rename to crates/presenter/src/host/launch_state_tests.rs
diff --git a/crates/app/src/host/logs.rs b/crates/presenter/src/host/logs.rs
similarity index 100%
rename from crates/app/src/host/logs.rs
rename to crates/presenter/src/host/logs.rs
diff --git a/crates/app/src/host/logs_tests.rs b/crates/presenter/src/host/logs_tests.rs
similarity index 100%
rename from crates/app/src/host/logs_tests.rs
rename to crates/presenter/src/host/logs_tests.rs
diff --git a/crates/app/src/host/meter.rs b/crates/presenter/src/host/meter.rs
similarity index 100%
rename from crates/app/src/host/meter.rs
rename to crates/presenter/src/host/meter.rs
diff --git a/crates/app/src/host/mod.rs b/crates/presenter/src/host/mod.rs
similarity index 98%
rename from crates/app/src/host/mod.rs
rename to crates/presenter/src/host/mod.rs
index 5d72d65..f0d1485 100644
--- a/crates/app/src/host/mod.rs
+++ b/crates/presenter/src/host/mod.rs
@@ -1,7 +1,7 @@
 //! 真实后端：把 core（game/launch/install/auth/java/diagnose/setting）装配成 GUI 的 host。
 //!
-//! 边界：本模块是整个 app 里**唯一**允许 `use unlucky_core::…` 的地方（连同 `settings_bridge`）；
-//! 出口只有 [`crate::dto`] 的快照/事件。线程模型：
+//! 边界：本模块是**整个 presenter crate 里唯一**允许 `use unlucky_core::…` 的地方（连同
+//! `settings_bridge`）；出口只有 [`crate::dto`] 的快照/事件。线程模型：
 //!
 //! ```text
 //! dispatch(AppCommand) ──► 立即动作（读盘/写设置）或 spawn 后台线程
diff --git a/crates/app/src/host/opener.rs b/crates/presenter/src/host/opener.rs
similarity index 100%
rename from crates/app/src/host/opener.rs
rename to crates/presenter/src/host/opener.rs
diff --git a/crates/app/src/host/settings.rs b/crates/presenter/src/host/settings.rs
similarity index 100%
rename from crates/app/src/host/settings.rs
rename to crates/presenter/src/host/settings.rs
diff --git a/crates/app/src/host/settings_tests.rs b/crates/presenter/src/host/settings_tests.rs
similarity index 100%
rename from crates/app/src/host/settings_tests.rs
rename to crates/presenter/src/host/settings_tests.rs
diff --git a/crates/app/src/host/versions.rs b/crates/presenter/src/host/versions.rs
similarity index 100%
rename from crates/app/src/host/versions.rs
rename to crates/presenter/src/host/versions.rs
diff --git a/crates/presenter/src/lib.rs b/crates/presenter/src/lib.rs
new file mode 100644
index 0000000..d9e96b1
--- /dev/null
+++ b/crates/presenter/src/lib.rs
@@ -0,0 +1,117 @@
+//! Unlucky-Launcher 的 **UI 框架无关宿主层**（presenter）。
+//!
+//! # 1. 这层为什么存在
+//!
+//! D26 的技术路线是「用 iced 重写 UI」。重写只应该换掉**渲染**，不该重写业务装配——
+//! 本 crate 就是被两个 UI 版共用的那一半：Slint 版（`crates/app`）与 iced 版
+//! （`crates/app-iced`）都从这里取 DTO、状态 reducer 与 host。Slint 退役后只剩 iced
+//! 依赖它，本 crate 不受影响。
+//!
+//! 判据（M85 已核）：这套代码原本住在 `crates/app/src`，但 `host/`（25 个文件）、
+//! `state.rs`、`settings_bridge.rs`、`dto/` 里**没有一处** UI 框架符号；它们依赖的只有
+//! 标准库、serde 与 `unlucky-core`。把它们留在 UI crate 里等于让 iced 重写跟着重写一遍
+//! 约 5400 行，白担行为漂移的风险。
+//!
+//! # 2. 对外表面（UI 侧的唯一入口）
+//!
+//! ```text
+//! host::CoreHost ──impl Backend──► dto::AppEvent ──► state::AppState::apply ──► dto 快照
+//!        ▲                                              │
+//!        └──────────── dto::AppCommand ◄────────────────┘
+//! ```
+//!
+//! | 模块 | 入口 | UI 侧怎么用 |
+//! | ---- | ---- | ----------- |
+//! | [`dto`] | [`dto::Backend`] / [`dto::AppCommand`] / [`dto::AppEvent`] / 各 `*View` 快照 | 派发指令、消费事件、把快照字段映射成视图模型 |
+//! | [`host`] | [`host::CoreHost`]（实现 [`dto::Backend`]）、[`host::HostEnv`] | 进程启动时构造一次，之后只当 `Box<dyn Backend>` 用 |
+//! | [`state`] | [`state::AppState`]（`apply` / `navigate` / 各页面字段） | **唯一**状态入口：事件进来先 `apply`，再从字段取值画 |
+//! | [`prefs`] | `UiPrefs` / `ThemeMode` / `TileSize` / `AppearancePrefs` / `keys` | 读字段做展示；不自己写盘 |
+//! | [`settings_bridge`] | `SettingsBridge`（`open` / `load` / `persist` / `reload_if_changed`） | 启动读一次、变更时写回、每拍问一次「变了吗」 |
+//! | [`theme`] | `CONFIG_POLL_TICKS` / `BACKGROUND_KEY` 一类纯判据、`tile_viewport` / `system_theme_value` | 「这一拍该不该重读/重建」由它回答，UI 只执行 |
+//! | [`router`] | `Route` / `Router` / `AiPanelMode` | 导航状态 |
+//! | [`dialogs`] | `DialogQueue` / `DialogRequest` | 模态队列 |
+//! | [`toast`] | `ToastCenter` / `Toast` | 非阻塞提示 |
+//! | [`wizard`] | `WizardState` | 新建实例向导的纯状态机 |
+//! | [`mock`] / [`mock_data`] | `MockBackend` / 样例数据 | 无数据根时的演示后端、UI 回归 |
+//! | [`backend`] | `AppOptions` / `build_backend` / `config_path` | 启动时选真实 host 还是 mock |
+//!
+//! # 3. UI 侧允许做什么、禁止做什么
+//!
+//! 允许（**只做展示与转发**）：
+//!
+//! - 把本 crate 的值翻译成框架类型（视图模型、颜色、图标、字符串）并灌进属性/`Element`；
+//! - 回调里把用户动作翻成 [`dto::AppCommand`] 交给 [`dto::Backend::dispatch`]，再 `drain_events()` 喂
+//!   [`state::AppState::apply`]——**不要**在本地做乐观回显（会话气泡/磁贴状态都以事件为准）；
+//! - 框架能力：窗口、定时器/订阅、图片解码与模糊层、截图落盘、字体加载。
+//!
+//! 禁止：
+//!
+//! - 在本 crate 里出现 Slint / iced / winit 类型（守门命令见 `crates/app/Cargo.toml` 的注释：
+//!   自指问题让那条命令不能写在本 crate 里，否则它自己就被抓出来了）；
+//! - UI 侧绕过 [`state::AppState::apply`] 直接改状态字段（会与事件流打架，磁贴/日志会漂）；
+//! - UI 侧直接 `use unlucky_core::…` 组装业务（读盘、起进程、拼路径、写设置一律走 host/bridge）；
+//! - UI 侧自己造 `<data root>` 路径：路径只从 [`host::HostEnv`] / [`settings_bridge`] 拿。
+//!
+//! # 4. iced 接线的推荐用法（骨架，伪代码）
+//!
+//! ```ignore
+//! // 1) 启动：选后端（数据根解析不出来自动退回 mock）
+//! let backend: Box<dyn Backend> = build_backend(&AppOptions::default());
+//! let bridge = SettingsBridge::open();          // 读盘一次，主题/外观看这里
+//! let state = AppState::new();
+//!
+//! // 2) 订阅：iced 的 30fps 订阅里推进一拍
+//! fn subscription() -> Subscription<Message> { iced::time::every(TICK).map(|_| Message::Tick) }
+//! fn update(&mut self, Message::Tick) {
+//!     backend.tick(TICK);                        // 后台线程的消息在这里汇聚
+//!     for event in backend.drain_events() { self.state.apply(event); }   // 唯一的写状态入口
+//!     if config_poll_due(self.ticks) {           // presenter 的纯判据
+//!         if let Some((appearance, theme)) = self.bridge.reload_if_changed() { … }
+//!     }
+//!     self.view = ViewModel::from(&self.state);  // 展示转换在 iced 侧做
+//! }
+//!
+//! // 3) 回调：用户动作 → AppCommand → 事件回流（不本地回显）
+//! fn update(&mut self, Message::Launch(id)) { self.dispatch(AppCommand::Launch(id)); }
+//! ```
+//!
+//! 要点：`state` / `bridge` / `backend` 三件由 UI 侧持有并驱动，`presenter` 不持有定时器也不
+//! 知道帧率；事件顺序以 `drain_events()` 的顺序为准（host 侧保证配对：`Install` 之后必有
+//! `InstallDone`、`LaunchStarted` 之后必有 `LaunchEnd`）。
+//!
+//! # 5. 留在 `crates/app`（Slint 侧）的东西，以及为什么
+//!
+//! | 留在 app | 为什么不能进 presenter |
+//! | -------- | ---------------------- |
+//! | `conv/` | 把 DTO 转成 **Slint 结构体**（UI 侧生成的视图模型类型），是 Slint 专属转换层 |
+//! | `ui_bind.rs` / `page_sync.rs` / `callbacks*.rs` | 持有 `MainWindow`、`ModelRc`、回调闭包，全是框架绑定 |
+//! | `theme_runtime.rs` / `appearance_bind.rs` | `impl Inner` 的方法，读写窗口属性与图片属性；其中的**纯判据**已抽到 [`theme`] |
+//! | `bg_image.rs` / `png.rs` | 解码/模糊/编码产出框架图片类型与像素缓冲，属渲染侧 |
+//! | `screenshot.rs` | Slint 快照通道（`Window::take_snapshot`） |
+//! | `main.rs` | `include_modules!()` 与窗口拉起 |
+//!
+//! # 6. 零 UI 依赖的证据命令
+//!
+//! 两条命令（`grep` 与 `cargo tree`）的原文与实测输出见 `crates/app/Cargo.toml` 的注释与 M85
+//! 的完成报告：本 crate 的依赖树里只有 serde / serde_json / unlucky-core（及其自身依赖）。
+
+// 关于 dead_code：host 里有一批「已定义、由单测覆盖、等 iced 页面接线才调用」的辅助函数
+// （`host::logs::session_finished`、`host::settings::clear_vendor_priority`、`loader_label`
+// 等）。它们原本住在 `crates/app` 里，由那边的 crate 级 `#![allow(dead_code)]` 一并放开；
+// 搬进 lib 之后「pub 但模块私有」会被判成死码。逐条 `#[allow]` 会把噪音藏进实现细节，
+// 这里沿用同一条策略统一放开，接线完成后再删掉本行暴露真死码。
+#![allow(dead_code)]
+
+pub mod backend;
+pub mod dialogs;
+pub mod dto;
+pub mod host;
+pub mod mock;
+pub mod mock_data;
+pub mod prefs;
+pub mod router;
+pub mod settings_bridge;
+pub mod state;
+pub mod theme;
+pub mod toast;
+pub mod wizard;
diff --git a/crates/app/src/mock.rs b/crates/presenter/src/mock.rs
similarity index 100%
rename from crates/app/src/mock.rs
rename to crates/presenter/src/mock.rs
diff --git a/crates/app/src/mock_data.rs b/crates/presenter/src/mock_data.rs
similarity index 100%
rename from crates/app/src/mock_data.rs
rename to crates/presenter/src/mock_data.rs
diff --git a/crates/app/src/prefs.rs b/crates/presenter/src/prefs.rs
similarity index 94%
rename from crates/app/src/prefs.rs
rename to crates/presenter/src/prefs.rs
index 2649907..683aee4 100644
--- a/crates/app/src/prefs.rs
+++ b/crates/presenter/src/prefs.rs
@@ -10,8 +10,8 @@ pub use unlucky_core::setting::appearance::BgFill;
 
 use crate::dto::VersionCategory;
 
-/// 预设强调色板（09 §104）。**必须**与 `ui/pages/settings-appearance.slint` 的 `swatch-colors`
-/// 同序同值：Slint 侧只回传索引，十六进制串由这张表给出（一处真相）。
+/// 预设强调色板（09 §104）。**必须**与 UI 侧设置页「外观」分组的色板控件同序同值：
+/// UI 侧只回传索引，十六进制串由这张表给出（一处真相）。
 pub const ACCENT_PRESETS: [&str; 8] = [
     "#0078D4", "#0F6CBD", "#107C10", "#9D5D00", "#C42B1C", "#8764B8", "#C239B3", "#00B7C3",
 ];
@@ -60,9 +60,9 @@ pub enum InstanceView {
 
 /// 主题三态（D17，P0 交付）：`appearance.theme_mode ∈ {light, dark, auto}`，出厂 auto。
 ///
-/// auto 由 `theme/tokens.slint` 读 Slint 原生 `Palette.color-scheme` 跟随系统（后端随 OS 热更）；
-/// light/dark 由 `Theme.theme-mode` 钉死**自绘体系**；std-widgets 内部件（ListView 滚动条 /
-/// ProgressIndicator / AboutSlint）目前仍跟随系统色，`Palette.color-scheme` 的钉死留 P1。
+/// `auto` = 跟随系统（由 UI 侧的令牌层读系统调色板，随 OS 热更；探测口径见
+/// [`crate::theme::system_theme_value`]）；`light` / `dark` 钉死**自绘体系**的取值。
+/// 三个取值怎么变成框架颜色是 UI 侧的事，本 crate 只给语义。
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
 pub enum ThemeMode {
     /// 跟随系统（默认）
diff --git a/crates/app/src/router.rs b/crates/presenter/src/router.rs
similarity index 100%
rename from crates/app/src/router.rs
rename to crates/presenter/src/router.rs
diff --git a/crates/app/src/settings_bridge.rs b/crates/presenter/src/settings_bridge.rs
similarity index 100%
rename from crates/app/src/settings_bridge.rs
rename to crates/presenter/src/settings_bridge.rs
diff --git a/crates/app/src/state.rs b/crates/presenter/src/state.rs
similarity index 97%
rename from crates/app/src/state.rs
rename to crates/presenter/src/state.rs
index c389eed..c928460 100644
--- a/crates/app/src/state.rs
+++ b/crates/presenter/src/state.rs
@@ -1,6 +1,6 @@
-//! UI 状态与 reducer：Slint 只负责渲染，所有状态变更都汇聚到 [`AppState::apply`]。
+//! UI 状态与 reducer：UI 框架只负责渲染，所有状态变更都汇聚到 [`AppState::apply`]。
 //!
-//! 数据流向：mock/host 后端 → [`crate::dto::AppEvent`] 队列 → `apply` → 状态字段 → Slint 属性。
+//! 数据流向：mock/host 后端 → [`crate::dto::AppEvent`] 队列 → `apply` → 状态字段 → UI 属性。
 //! 偏好项在 [`crate::prefs`] 里登记了持久化键名，core::setting 的 schema 落地后按这些键读写。
 
 use crate::dialogs::DialogQueue;
@@ -56,7 +56,7 @@ impl AiSession {
     }
 }
 
-/// 磁贴网格单元：位置由 [`grid_positions`] 算好，Slint 只消费 row/col。
+/// 磁贴网格单元：位置由 [`grid_positions`] 算好，UI 侧只消费 row/col。
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub struct TileCell<'a> {
     /// 实例数据
@@ -69,7 +69,7 @@ pub struct TileCell<'a> {
 
 /// 纯函数：把 n 个磁贴摊到 `columns` 列的网格上，返回 `(row, col)`。
 ///
-/// 特意放在 Rust 侧：Slint DSL 里做整数除法会引入隐式浮点，且这段逻辑可以单测。
+/// 特意放在 Rust 侧：声明式 UI 的表达式里做整数除法容易引出隐式浮点，且这段逻辑可以单测。
 pub fn grid_positions(count: usize, columns: usize) -> Vec<(usize, usize)> {
     let columns = columns.max(1);
     (0..count)
diff --git a/crates/app/src/state_tests.rs b/crates/presenter/src/state_tests.rs
similarity index 100%
rename from crates/app/src/state_tests.rs
rename to crates/presenter/src/state_tests.rs
diff --git a/crates/presenter/src/theme.rs b/crates/presenter/src/theme.rs
new file mode 100644
index 0000000..42d39f2
--- /dev/null
+++ b/crates/presenter/src/theme.rs
@@ -0,0 +1,165 @@
+//! 主题与外观的**纯**判据：轮询节拍、背景图缓存键与量化、系统主题取值。
+//!
+//! 这一层原本混在 `crates/app` 的 `ui_bind.rs` / `theme_runtime.rs` 里，与「把值灌进窗口属性」
+//! 的绑定代码缠在一起，于是两个 UI 版都得各写一遍。抽到这里的只有**判据**：什么时候该重读配置、
+//! 什么时候该重建背景图、系统主题该报哪个值。灌属性仍然由 UI 侧做，本模块不碰任何框架类型。
+
+use crate::prefs::BgFill;
+
+/// 配置热切轮询间隔（拍数，33ms/拍 → 约 1s 一次 `mtime` 比对，AI/CLI 改完下一拍即生效）。
+pub const CONFIG_POLL_TICKS: u64 = 30;
+
+/// 系统主题兜底轮询间隔（拍数）：只在 `auto` 且后端不认识系统主题时启动（约 3s）。
+pub const SYSTEM_THEME_POLL_TICKS: u64 = 90;
+
+/// tile 模式重建画布的窗口尺寸粒度（像素）：避免拖动窗口时反复重算平铺画布。
+pub const TILE_REGENERATE_STEP: u32 = 128;
+
+/// 系统主题取值（UI 侧根组件属性就用这三个值：0 未知 / 1 浅色 / 2 深色）。
+pub const SYSTEM_THEME_UNKNOWN: i32 = 0;
+/// 浅色。
+pub const SYSTEM_THEME_LIGHT: i32 = 1;
+/// 深色。
+pub const SYSTEM_THEME_DARK: i32 = 2;
+
+/// 背景图加工输入（值相同就不重新解码）。
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct BackgroundKey {
+    /// 背景图路径
+    pub path: String,
+    /// 填充模式
+    pub fill: BgFill,
+    /// tile 用的窗口尺寸（按 [`TILE_REGENERATE_STEP`] 量化；cover/contain 恒为 (0, 0)）
+    pub viewport: (u32, u32),
+}
+
+/// 本拍是否该比对一次配置文件 `mtime`（热切的采样点）。
+pub fn config_poll_due(ticks: u64) -> bool {
+    ticks.is_multiple_of(CONFIG_POLL_TICKS)
+}
+
+/// 本拍是否该兜底探测系统主题。
+///
+/// 启动时先探一次（`probed == false`），之后只在「主题是 auto + 后端不认识系统主题」时
+/// 按 [`SYSTEM_THEME_POLL_TICKS`] 兜底轮询。
+pub fn system_theme_poll_due(probed: bool, auto: bool, backend_known: bool, ticks: u64) -> bool {
+    !probed || (auto && !backend_known && ticks.is_multiple_of(SYSTEM_THEME_POLL_TICKS))
+}
+
+/// 系统主题取值（纯映射，便于单测）。
+pub fn system_theme_code(theme: unlucky_core::platform::theme_probe::SystemTheme) -> i32 {
+    use unlucky_core::platform::theme_probe::SystemTheme;
+    match theme {
+        SystemTheme::Light => SYSTEM_THEME_LIGHT,
+        SystemTheme::Dark => SYSTEM_THEME_DARK,
+        SystemTheme::Unknown => SYSTEM_THEME_UNKNOWN,
+    }
+}
+
+/// 探测本机系统主题并给出 UI 侧属性值。
+pub fn system_theme_value() -> i32 {
+    system_theme_code(unlucky_core::platform::theme_probe::probe())
+}
+
+/// tile 画布的窗口尺寸（量化到 [`TILE_REGENERATE_STEP`]，避免拖动窗口时反复重算）。
+///
+/// 非 tile 模式恒为 (0, 0)：cover/contain 不依赖窗口尺寸，缩放只让渲染器拉伸。
+pub fn tile_viewport(fill: BgFill, size: (u32, u32)) -> (u32, u32) {
+    if fill != BgFill::Tile {
+        return (0, 0);
+    }
+    (
+        size.0 / TILE_REGENERATE_STEP * TILE_REGENERATE_STEP,
+        size.1 / TILE_REGENERATE_STEP * TILE_REGENERATE_STEP,
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{
+        config_poll_due, system_theme_code, system_theme_poll_due, tile_viewport, BackgroundKey,
+        CONFIG_POLL_TICKS, SYSTEM_THEME_DARK, SYSTEM_THEME_LIGHT, SYSTEM_THEME_POLL_TICKS,
+        SYSTEM_THEME_UNKNOWN, TILE_REGENERATE_STEP,
+    };
+    use crate::prefs::BgFill;
+    use unlucky_core::platform::theme_probe::SystemTheme;
+
+    #[test]
+    fn config_poll_fires_every_interval() {
+        assert!(config_poll_due(0));
+        assert!(!config_poll_due(1));
+        assert!(config_poll_due(CONFIG_POLL_TICKS));
+        assert!(!config_poll_due(CONFIG_POLL_TICKS + 1));
+    }
+
+    #[test]
+    fn system_theme_probe_backs_off_after_first_read() {
+        // 启动时无条件探一次
+        assert!(system_theme_poll_due(false, false, true, 1));
+        // 探过、主题非 auto：不再轮询
+        assert!(!system_theme_poll_due(
+            true,
+            false,
+            false,
+            SYSTEM_THEME_POLL_TICKS
+        ));
+        // 探过、auto、后端认识系统主题：不再轮询
+        assert!(!system_theme_poll_due(
+            true,
+            true,
+            true,
+            SYSTEM_THEME_POLL_TICKS
+        ));
+        // 探过、auto、后端不认识：按间隔兜底
+        assert!(!system_theme_poll_due(
+            true,
+            true,
+            false,
+            SYSTEM_THEME_POLL_TICKS - 1
+        ));
+        assert!(system_theme_poll_due(
+            true,
+            true,
+            false,
+            SYSTEM_THEME_POLL_TICKS
+        ));
+    }
+
+    #[test]
+    fn system_theme_codes_are_stable() {
+        assert_eq!(
+            system_theme_code(SystemTheme::Unknown),
+            SYSTEM_THEME_UNKNOWN
+        );
+        assert_eq!(system_theme_code(SystemTheme::Light), SYSTEM_THEME_LIGHT);
+        assert_eq!(system_theme_code(SystemTheme::Dark), SYSTEM_THEME_DARK);
+    }
+
+    #[test]
+    fn tile_viewport_quantizes_and_ignores_other_fills() {
+        assert_eq!(tile_viewport(BgFill::Cover, (1180, 760)), (0, 0));
+        assert_eq!(tile_viewport(BgFill::Contain, (1180, 760)), (0, 0));
+        let (width, height) = tile_viewport(BgFill::Tile, (1180, 760));
+        assert_eq!(width % TILE_REGENERATE_STEP, 0);
+        assert_eq!(height % TILE_REGENERATE_STEP, 0);
+        assert_eq!((width, height), (1152, 768));
+    }
+
+    #[test]
+    fn background_key_compares_by_value() {
+        let key = BackgroundKey {
+            path: "a.png".to_string(),
+            fill: BgFill::Tile,
+            viewport: (256, 256),
+        };
+        assert_eq!(key.clone(), key);
+        assert_ne!(
+            key,
+            BackgroundKey {
+                path: "a.png".to_string(),
+                fill: BgFill::Tile,
+                viewport: (128, 256),
+            }
+        );
+    }
+}
diff --git a/crates/app/src/toast.rs b/crates/presenter/src/toast.rs
similarity index 100%
rename from crates/app/src/toast.rs
rename to crates/presenter/src/toast.rs
diff --git a/crates/app/src/wizard.rs b/crates/presenter/src/wizard.rs
similarity index 100%
rename from crates/app/src/wizard.rs
rename to crates/presenter/src/wizard.rs