fix(app-iced): M90 r2 —— 找回窗口装饰 + 按需节拍 + 数据根一致 + 假绿守卫

复审 P1-1（产品页丢窗口装饰）：shell 加内容槽位 view_with_content(ui, nav, title, content, forced)，
app/view.rs 把 pages::page(...) 塞进真外壳；shell::view 保留给 Route::Agent 回落（删了会让私有
view/nav::rail 变死代码，-D warnings 红）。content() 拆到 shell/fallback.rs 让 mod.rs 回到 365 行。
1180 浅/深新图右上角三个 caption 键实测：ink 中心 y=23.5（栏高 48 的一半）、x 中心 1064.5/1110.5/
1156.5 = 46px 分档的 1065/1111/1157（±0.5px），close 命中区右缘 = 1180 窗角。
偏离 #7 改写成「交互面缺失」并注明本轮已修。

P1-2（harness.rs 402 行）：tests 外置到 pages/harness/tests.rs（343 + 64 行）；
components/gate.rs 的行数守门从走查 components/ 扩到 src/**（新测试当场抓出 app/tests.rs 416 行，
已按同样办法拆成 app/tests.rs + app/tests/presenter.rs）。

P2-1（常驻重绘 + 每拍重建模型）：subscription 只在「截图 / 有 Busy-Running / 有 toast / 3 s 派发
观察窗」时订阅 window::frames()；refresh_view 加 view_dirty 门。实测交互模式 9 s：只有 2 行 tick
trace（n=30/60，观察窗内），之后 6.5 s 一条都没有；refreshes 全程停在 7。

P2-2（两个数据根）：--data-dir 时 SettingsBridge::with_path(config_path(root))，与后端同根。

P3-2（假绿）：新增 RecorderBackend（dispatch 只记账、drain_events 恒空）+ launching_only_dispatches
_and_never_echoes_locally；植入本地回显后该测试实测转红（status 变 Downloading · 0%、can_stop 翻
true），撤回后转绿。
P3-3：尺寸字面量守门目录加 app；P3-1：--force-state 经 pages::Model::forced 作用到产品页控件
（hover 图里页头/列表/动作行/rail/caption 全部可见状态层）；视觉 P2-2：加载器名统一走 badge()。

gallery 回归改口径：r2 与「主线 + r1」的 gallery 逐字节相同（cmp IDENTICAL）；与 r1 记的
c825e1a 基线不同，差异来自主线 M86/M88 的令牌收口，不是本 mission。

crates/app-iced/src/pages/instances.rs

@@ -30,6 +30,7 @@
 
 mod data;
 mod demo;
+mod detail;
 
 #[cfg(test)]
 mod tests;
@@ -47,46 +48,54 @@ use unlucky_design::icons::IconKind;
 use unlucky_design::shape::ShapeScale;
 use unlucky_design::spacing::Space;
 use unlucky_design::typography::TypeRole;
-use unlucky_presenter::router::Route;
 
 use crate::app::components::buttons::{self, Button};
-use crate::app::components::divider;
+use crate::app::components::interaction::Interaction;
 use crate::app::components::navigation::list_item::{list_item, ListItem};
 use crate::theme::Ui;
+use unlucky_presenter::router::Route;
 
 use super::frame::{self, Header};
-use super::layout::{self, FrameMetrics, PageLayout};
-use super::model::{Detail, Instances, Row};
+use super::layout::{FrameMetrics, PageLayout};
+use super::model::{Instances, Model, Row};
 use super::{Action, Message};
 
 /// 列表行的间距（`Space::X1`；与 M84 同值，行高差异全部来自 `ListItem` 自己的几何）。
 const ROW_GAP: Space = Space::X1;
 
 /// 整页（`block.detail = None` 时详情区显示空态）。
-pub fn view<'a>(ui: &'a Ui, metrics: FrameMetrics, block: &'a Instances) -> Element<'a, Message> {
+pub fn view<'a>(ui: &'a Ui, metrics: FrameMetrics, model: &'a Model) -> Element<'a, Message> {
+    let block = &model.instances;
+    let forced = model.forced;
     let header = Header::new("Instances")
         .subtitle("Local versions and their mod loaders")
         .action(buttons::text(
             ui,
-            Button::new("New instance", Message::Action(Action::NewInstance)),
+            forced_state(
+                Button::new("New instance", Message::Action(Action::NewInstance)),
+                forced,
+            ),
         ))
         .action(buttons::text(
             ui,
-            Button::new("Import", Message::Action(Action::Import)),
+            forced_state(
+                Button::new("Import", Message::Action(Action::Import)),
+                forced,
+            ),
         ));
 
     let body = match metrics.layout {
         PageLayout::ListDetail => frame::panes(
             metrics,
-            list_column(ui, block),
+            list_column(ui, block, forced),
             match &block.detail {
-                Some(detail) => detail_column(ui, metrics, detail),
-                None => detail_empty(ui),
+                Some(detail) => detail::detail_column(ui, metrics, detail, forced),
+                None => detail::detail_empty(ui),
             },
         ),
         _ => match &block.detail {
-            Some(detail) => narrow_detail(ui, metrics, detail),
-            None => frame::single_column(metrics, detail_empty(ui)),
+            Some(detail) => detail::narrow_detail(ui, metrics, detail, forced),
+            None => frame::single_column(metrics, detail::detail_empty(ui)),
         },
     };
 
@@ -95,7 +104,11 @@ pub fn view<'a>(ui: &'a Ui, metrics: FrameMetrics, block: &'a Instances) -> Elem
 
 // --------------------------------------------------------------- 列表列
 
-fn list_column<'a>(ui: &'a Ui, block: &'a Instances) -> Element<'a, Message> {
+fn list_column<'a>(
+    ui: &'a Ui,
+    block: &'a Instances,
+    forced: Option<Interaction>,
+) -> Element<'a, Message> {
     let head = container(
         row![
             container(frame::text_role(
@@ -130,7 +143,7 @@ fn list_column<'a>(ui: &'a Ui, block: &'a Instances) -> Element<'a, Message> {
         block
             .rows
             .iter()
-            .map(|entry| list_row(ui, entry, is_selected(block, entry)))
+            .map(|entry| list_row(ui, entry, is_selected(block, entry), forced))
             .collect::<Vec<_>>(),
     )
     .spacing(ui.space(ROW_GAP))
@@ -169,11 +182,27 @@ fn is_selected(block: &Instances, entry: &Row) -> bool {
         .is_some_and(|detail| detail.id == entry.id)
 }
 
+/// `--force-state` 的落点：只改**画出来的**状态，不动任何状态机（cli `ForcedState` 的同一条纪律）。
+pub(super) fn forced_state<'a, M>(
+    button: Button<'a, M>,
+    forced: Option<Interaction>,
+) -> Button<'a, M> {
+    match forced {
+        Some(state) => button.state(state),
+        None => button,
+    }
+}
+
 /// 一行（`ListItem` 的两/三行档：overline = 运行状态，headline = 名字，supporting = 版本 + 加载器）。
 ///
 /// 点一行 = **压一层路由栈**（`Route::Detail(id)`），页面自己不留「选中项」副本——
 /// 于是「当前选中」与「返回栈」永远是同一份真相（`presenter::router`）。
-fn list_row<'a>(ui: &'a Ui, entry: &'a Row, selected: bool) -> Element<'a, Message> {
+fn list_row<'a>(
+    ui: &'a Ui,
+    entry: &'a Row,
+    selected: bool,
+    forced: Option<Interaction>,
+) -> Element<'a, Message> {
     let mut item = ListItem::new(
         entry.name.as_str(),
         Message::Navigate(Route::Detail(entry.id.clone())),
@@ -188,194 +217,9 @@ fn list_row<'a>(ui: &'a Ui, entry: &'a Row, selected: bool) -> Element<'a, Messa
     if selected {
         item = item.selected();
     }
+    if let Some(state) = forced {
+        item = item.state(state);
+    }
 
     list_item(ui, item)
 }
-
-// --------------------------------------------------------------- 详情列
-
-fn detail_column<'a>(
-    ui: &'a Ui,
-    metrics: FrameMetrics,
-    detail: &'a Detail,
-) -> Element<'a, Message> {
-    let mut body = column![
-        detail_head(ui, detail),
-        meta_grid(ui, metrics, detail),
-        divider::full(ui),
-    ]
-    .spacing(ui.space(Space::X4))
-    .width(Length::Fill);
-
-    body = push_text(ui, body, detail);
-
-    // 页头 + 元信息网格 + **一条**分隔线以下才是正文与操作区（M84 那两条线是占位时期的排版残留）
-    frame::left_aligned(metrics.column, body.push(action_row(ui)))
-}
-
-fn narrow_detail<'a>(
-    ui: &'a Ui,
-    metrics: FrameMetrics,
-    detail: &'a Detail,
-) -> Element<'a, Message> {
-    // 窄窗：列表退成上一屏，本屏只放详情（官方 compact 的 list-detail 口径）。
-    let mut body = column![
-        row![buttons::text(
-            ui,
-            Button::new("Back to instances", Message::Navigate(Route::Instances)),
-        )]
-        .width(Length::Fill)
-        .align_y(Alignment::Center),
-        detail_head(ui, detail),
-        meta_grid(ui, metrics, detail),
-        divider::full(ui),
-    ]
-    .spacing(ui.space(Space::X4))
-    .width(Length::Fill);
-
-    body = push_text(ui, body, detail);
-
-    body = body.push(frame::text_role(
-        ui,
-        TypeRole::BodySmall,
-        false,
-        "Below 840 px the list and the detail share one column, so opening an instance replaces \
-         this screen (full-page switch). Widen the window to see both panes again.",
-        ui.color(Role::OnSurfaceVariant),
-    ));
-
-    frame::single_column(metrics, body.push(action_row(ui)))
-}
-
-/// 正文段（演示数据才有）与运行状态行（真数据才有）——两者都是可选的，顺序固定。
-fn push_text<'a>(
-    ui: &'a Ui,
-    mut body: iced::widget::Column<'a, Message>,
-    detail: &'a Detail,
-) -> iced::widget::Column<'a, Message> {
-    if let Some(note) = &detail.note {
-        body = body.push(frame::text_role(
-            ui,
-            TypeRole::BodyMedium,
-            false,
-            note.as_str(),
-            ui.color(Role::OnSurfaceVariant),
-        ));
-    }
-    if let Some(status) = &detail.status {
-        body = body.push(frame::text_role(
-            ui,
-            TypeRole::BodyMedium,
-            false,
-            status.as_str(),
-            ui.color(Role::OnSurface),
-        ));
-    }
-    body
-}
-
-fn detail_head<'a>(ui: &'a Ui, detail: &'a Detail) -> Element<'a, Message> {
-    let titles = column![
-        frame::text_role(
-            ui,
-            TypeRole::TitleLarge,
-            true,
-            detail.name.as_str(),
-            ui.color(Role::OnSurface)
-        ),
-        frame::text_role(
-            ui,
-            TypeRole::BodySmall,
-            false,
-            detail.subtitle.as_str(),
-            ui.color(Role::OnSurfaceVariant),
-        ),
-    ]
-    .spacing(ui.space(Space::X1))
-    .width(Length::Fill);
-
-    // 主操作：**全屏唯一**实心 accent（rubric K2）。不可用时退化成禁用态（只清消息，不改身份）。
-    let launch = if detail.can_launch {
-        buttons::filled(ui, Button::new("Play", Message::Launch(detail.id.clone())))
-    } else {
-        buttons::filled(ui, Button::disabled("Play"))
-    };
-    let stop = if detail.can_stop {
-        buttons::text(ui, Button::new("Stop", Message::Stop(detail.id.clone())))
-    } else {
-        buttons::text(ui, Button::disabled("Stop"))
-    };
-
-    row![titles, launch, stop]
-        .spacing(ui.space(Space::X2))
-        .width(Length::Fill)
-        .align_y(Alignment::Center)
-        .into()
-}
-
-/// 元信息网格：列数由 [`layout::meta_columns`]（按正文列宽）决定 —— **1180 与 900 都是 2 列**。
-///
-/// 3 列需要 `3 × META_CARD_MIN_WIDTH + 2 × META_GAP` = 504px，而行宽上限是 424，**数学上不可行**；
-/// 硬塞回 3 列会让 `NeoForge 20.4.237`（118px）这类值按词折行、同排卡底不齐。
-fn meta_grid<'a>(ui: &'a Ui, metrics: FrameMetrics, detail: &'a Detail) -> Element<'a, Message> {
-    let mut grid = column![].spacing(layout::META_GAP).width(Length::Fill);
-    let columns = metrics.meta_columns.clamp(1, detail.meta.len().max(1));
-
-    for chunk in detail.meta.chunks(columns) {
-        let mut cells_row = row![].spacing(layout::META_GAP).width(Length::Fill);
-        for cell in chunk {
-            let card = frame::card(
-                ui,
-                column![
-                    frame::text_role(
-                        ui,
-                        TypeRole::LabelMedium,
-                        false,
-                        cell.label.as_str(),
-                        ui.color(Role::OnSurfaceVariant),
-                    ),
-                    frame::text_role(
-                        ui,
-                        TypeRole::BodyMedium,
-                        false,
-                        cell.value.as_str(),
-                        ui.color(Role::OnSurface)
-                    ),
-                ]
-                .spacing(ui.space(Space::X1))
-                .width(Length::Fill),
-            );
-            cells_row = cells_row.push(container(card).width(Length::Fill));
-        }
-        grid = grid.push(cells_row);
-    }
-
-    grid.into()
-}
-
-fn action_row<'a>(ui: &'a Ui) -> Element<'a, Message> {
-    row![
-        buttons::text(
-            ui,
-            Button::new("Duplicate", Message::Action(Action::Duplicate))
-        ),
-        buttons::text(
-            ui,
-            Button::new("Open folder", Message::Action(Action::OpenFolder))
-        ),
-        buttons::text(ui, Button::new("Delete", Message::Action(Action::Delete))),
-    ]
-    .spacing(ui.space(Space::X2))
-    .align_y(Alignment::Center)
-    .into()
-}
-
-fn detail_empty<'a>(ui: &'a Ui) -> Element<'a, Message> {
-    frame::empty_state(
-        ui,
-        IconKind::Instances,
-        "No instance selected",
-        "Pick an instance on the left to see its version, loader and launch options.",
-        Vec::new(),
-    )
-}