refactor(app-iced): 语言行从 general.rs 纯搬移到 general/language.rs（M285 前置）

general.rs 390 行、撞 400 行硬线，而 M285 要给语言行三枚 chip 接 forced。
切法与既有的 general/theme.rs 同构（一个行控件一个文件）：正文 view + chip +
chip_style。语句逐字节搬移（去缩进去可见性后 diff 退出码 0），只把
fn language_row 改名成 pub(super) fn view（与 theme::view 同一入口命名）。

general.rs 390 → 245 行；language.rs 170 行。

crates/app-iced/src/pages/settings/general.rs

@@ -38,20 +38,15 @@
 //!
 //! 分组元数据只有一份（这里的 [`GROUP`]）：`settings/mod.rs` 的 `GROUPS` 直接引用它。
 
-use iced::border::Radius;
-use iced::widget::{button, column, container, row};
-use iced::{
-    Alignment, Background, Border, Color, Element, Length, Padding, Shadow, Theme as IcedTheme,
-};
+use iced::widget::{column, container, row};
+use iced::{Alignment, Element, Length, Padding};
 
 use unlucky_design::color::Role;
 use unlucky_design::icons::IconKind;
 use unlucky_design::spacing::Space;
 use unlucky_design::typography::TypeRole;
 use unlucky_i18n::catalog::Key;
-use unlucky_i18n::LangChoice;
 
-use crate::app::components::interaction::{self, Interaction};
 use crate::fonts::install::{CjkInstall, FetchClass};
 use crate::pages::{frame, Language, Message};
 use crate::theme::Ui;
@@ -59,6 +54,7 @@ use crate::theme::Ui;
 use super::frame::{card, divider};
 use super::{Group, States};
 
+mod language;
 mod theme;
 
 /// General 分组（左列名固定英文：左列是**导航**，与导航轨同源，不进 catalog）。
@@ -79,7 +75,7 @@ pub(super) const GROUP: Group = Group {
 pub(super) fn body<'a>(ui: &'a Ui, states: States<'a>, language: Language) -> Element<'a, Message> {
     let catalog = language.effective.catalog();
     let mut stacked = column![].spacing(0.0).width(Length::Fill);
-    stacked = stacked.push(language_row(ui, language));
+    stacked = stacked.push(language::view(ui, language));
     // M168（D28 后半）：中文字体的下载状态行。紧贴语言行——用户在这里手选中文，反馈就该在这行下面，
     // 而不是等他切到别的页面才发现「刚才那几秒在干嘛」。
     stacked = stacked.push(divider(ui));
@@ -215,66 +211,6 @@ fn font_row<'a>(ui: &'a Ui, language: Language) -> Element<'a, Message> {
     stacked.into()
 }
 
-/// 语言行：标题 + 生效语言回显 + 三档互斥按钮 + 一句说明。
-fn language_row<'a>(ui: &'a Ui, language: Language) -> Element<'a, Message> {
-    let catalog = language.effective.catalog();
-    let effective = LangChoice::Fixed(language.effective).label_key();
-
-    let head = row![
-        container(frame::text_role(
-            ui,
-            TypeRole::BodyMedium,
-            false,
-            catalog.text(Key::SettingsLanguage),
-            ui.color(Role::OnSurface),
-        ))
-        .width(Length::Fill)
-        .align_y(Alignment::Center),
-        frame::text_role_owned(
-            ui,
-            TypeRole::LabelLarge,
-            true,
-            catalog.render(
-                Key::SettingsLanguageEffective,
-                &[("language", catalog.text(effective))],
-            ),
-            ui.color(Role::OnPrimaryFixedVariant),
-        ),
-    ]
-    .width(Length::Fill)
-    .align_y(Alignment::Center);
-
-    let chips = row(LangChoice::ALL
-        .iter()
-        .map(|choice| {
-            chip(
-                ui,
-                catalog.text(choice.label_key()),
-                *choice == language.choice,
-                *choice,
-            )
-        })
-        .collect::<Vec<_>>())
-    .spacing(ui.space(Space::X1))
-    .align_y(Alignment::Center);
-
-    column![
-        head,
-        chips,
-        frame::text_role(
-            ui,
-            TypeRole::BodySmall,
-            false,
-            catalog.text(Key::SettingsLanguageHint),
-            ui.color(Role::OnSurfaceVariant),
-        ),
-    ]
-    .spacing(ui.space(Space::X1))
-    .width(Length::Fill)
-    .padding(Padding::from([ui.space(Space::X2), 0.0]))
-    .into()
-}
-
 /// 一个只读的「标签 + 取值」行（与 `frame::demo_card` 的一行同高同排版）。
 fn setting_row<'a>(ui: &'a Ui, label: &'a str, value: &'a str) -> Element<'a, Message> {
     let height = ui.metrics().control_height + Space::X2.dp();
@@ -302,89 +238,3 @@ fn setting_row<'a>(ui: &'a Ui, label: &'a str, value: &'a str) -> Element<'a, Me
     .align_y(Alignment::Center)
     .into()
 }
-
-/// 一个互斥按钮（选中态 `SecondaryContainer`，未选中透明 + `OnSurfaceVariant`）。
-///
-/// 与 `pages/appearance/section/mod.rs` 的 `choice` 同款几何，但文案来自 catalog（那份是英文基线）。
-///
-/// **几何（M229）**：取规格卡的 chip（高 32、圆角 8、内距 16、未选中 1px `OutlineVariant`），
-/// 与同屏的主题三档 chips 完全同源——两行都是「并排的互斥筛选」，长得不一样会让读者以为是
-/// 两种控件（M229 第一版就是这样：语言 40 高药丸、主题 32 高方角，出图一眼就不齐）。
-fn chip<'a>(ui: &'a Ui, text: &'a str, selected: bool, choice: LangChoice) -> Element<'a, Message> {
-    let box_ = unlucky_design::inkcat::metrics::CHIP;
-    let height = box_.height;
-    let content_color = if selected {
-        ui.color(Role::OnSecondaryContainer)
-    } else {
-        ui.color(Role::OnSurfaceVariant)
-    };
-    let border_color = ui.color(Role::OutlineVariant);
-    let stroke = crate::theme::STROKE_PX;
-    let radius = ui.radius(box_.shape, height);
-
-    button(
-        container(frame::text_role(
-            ui,
-            TypeRole::LabelLarge,
-            selected,
-            text,
-            content_color,
-        ))
-        .align_y(Alignment::Center),
-    )
-    .height(height)
-    .padding(Padding::from([
-        0.0,
-        unlucky_design::inkcat::metrics::CHIP_PAD_X,
-    ]))
-    .style(chip_style(
-        ui,
-        selected,
-        content_color,
-        border_color,
-        stroke,
-        radius,
-    ))
-    .on_press(Message::Language(choice))
-    .into()
-}
-
-/// [`chip`] 的样式闭包（抽成自由函数：单测要**直接**喂 `Hovered` / `Pressed` 两态）。
-///
-/// - **α 只从 [`Interaction`] 来**：hover 8% / pressed 10%（M3）。M284 之前两种态合并成一条
-///   `matches!(status, Hovered | Pressed)` 分支、都叠 `StateLayer::Hover`，按下于是被压成 8%；
-/// - **合成底是 [`frame::BASE`]**（M237：这一组住在 `frame::card` 里，状态层叠卡底而不是画布）。
-fn chip_style<'a>(
-    ui: &'a Ui,
-    selected: bool,
-    content_color: Color,
-    border_color: Color,
-    stroke: f32,
-    radius: Radius,
-) -> impl Fn(&IcedTheme, button::Status) -> button::Style + 'a {
-    move |_theme, status| {
-        let background = if selected {
-            Some(Background::Color(ui.color(Role::SecondaryContainer)))
-        } else {
-            interaction::layer_color(
-                ui,
-                Interaction::from_status(status),
-                Role::OnSurface,
-                frame::BASE.role(),
-            )
-            .map(Background::Color)
-        };
-
-        button::Style {
-            background,
-            text_color: content_color,
-            border: Border {
-                color: border_color,
-                width: if selected { 0.0 } else { stroke },
-                radius,
-            },
-            shadow: Shadow::default(),
-            snap: true,
-        }
-    }
-}

crates/app-iced/src/pages/settings/general/language.rs

@@ -0,0 +1,170 @@
+//! 设置页 General 组的**语言行**（M285 `LANGSET`：从 `general.rs` 纯搬移）。
+//!
+//! 搬出来的理由只有行数：`general.rs` 390 行、撞 400 行硬线（`components/gate.rs`），
+//! 而 M285 要给这一行的三枚互斥按钮接 `forced: Option<Interaction>`（`--force-state` 直通）。
+//! 切法与 [`super::theme`] 完全同构——**一个行控件一个文件**：正文 [`view`] + 它的 [`chip`]
+//! + [`chip_style`]（样式闭包抽成自由函数，单测才能直接喂 `Hovered` / `Pressed` 两态）。
+//!
+//! 搬移是逐字搬的：三个函数的语句、注释一个字没动。
+
+use iced::border::Radius;
+use iced::widget::{button, column, container, row};
+use iced::{
+    Alignment, Background, Border, Color, Element, Length, Padding, Shadow, Theme as IcedTheme,
+};
+
+use unlucky_design::color::Role;
+use unlucky_design::spacing::Space;
+use unlucky_design::typography::TypeRole;
+use unlucky_i18n::catalog::Key;
+use unlucky_i18n::LangChoice;
+
+use crate::app::components::interaction::{self, Interaction};
+use crate::pages::{frame, Language, Message};
+use crate::theme::Ui;
+
+/// 语言行：标题 + 生效语言回显 + 三档互斥按钮 + 一句说明。
+pub(super) fn view<'a>(ui: &'a Ui, language: Language) -> Element<'a, Message> {
+    let catalog = language.effective.catalog();
+    let effective = LangChoice::Fixed(language.effective).label_key();
+
+    let head = row![
+        container(frame::text_role(
+            ui,
+            TypeRole::BodyMedium,
+            false,
+            catalog.text(Key::SettingsLanguage),
+            ui.color(Role::OnSurface),
+        ))
+        .width(Length::Fill)
+        .align_y(Alignment::Center),
+        frame::text_role_owned(
+            ui,
+            TypeRole::LabelLarge,
+            true,
+            catalog.render(
+                Key::SettingsLanguageEffective,
+                &[("language", catalog.text(effective))],
+            ),
+            ui.color(Role::OnPrimaryFixedVariant),
+        ),
+    ]
+    .width(Length::Fill)
+    .align_y(Alignment::Center);
+
+    let chips = row(LangChoice::ALL
+        .iter()
+        .map(|choice| {
+            chip(
+                ui,
+                catalog.text(choice.label_key()),
+                *choice == language.choice,
+                *choice,
+            )
+        })
+        .collect::<Vec<_>>())
+    .spacing(ui.space(Space::X1))
+    .align_y(Alignment::Center);
+
+    column![
+        head,
+        chips,
+        frame::text_role(
+            ui,
+            TypeRole::BodySmall,
+            false,
+            catalog.text(Key::SettingsLanguageHint),
+            ui.color(Role::OnSurfaceVariant),
+        ),
+    ]
+    .spacing(ui.space(Space::X1))
+    .width(Length::Fill)
+    .padding(Padding::from([ui.space(Space::X2), 0.0]))
+    .into()
+}
+
+/// 一个互斥按钮（选中态 `SecondaryContainer`，未选中透明 + `OnSurfaceVariant`）。
+///
+/// 与 `pages/appearance/section/mod.rs` 的 `choice` 同款几何，但文案来自 catalog（那份是英文基线）。
+///
+/// **几何（M229）**：取规格卡的 chip（高 32、圆角 8、内距 16、未选中 1px `OutlineVariant`），
+/// 与同屏的主题三档 chips 完全同源——两行都是「并排的互斥筛选」，长得不一样会让读者以为是
+/// 两种控件（M229 第一版就是这样：语言 40 高药丸、主题 32 高方角，出图一眼就不齐）。
+fn chip<'a>(ui: &'a Ui, text: &'a str, selected: bool, choice: LangChoice) -> Element<'a, Message> {
+    let box_ = unlucky_design::inkcat::metrics::CHIP;
+    let height = box_.height;
+    let content_color = if selected {
+        ui.color(Role::OnSecondaryContainer)
+    } else {
+        ui.color(Role::OnSurfaceVariant)
+    };
+    let border_color = ui.color(Role::OutlineVariant);
+    let stroke = crate::theme::STROKE_PX;
+    let radius = ui.radius(box_.shape, height);
+
+    button(
+        container(frame::text_role(
+            ui,
+            TypeRole::LabelLarge,
+            selected,
+            text,
+            content_color,
+        ))
+        .align_y(Alignment::Center),
+    )
+    .height(height)
+    .padding(Padding::from([
+        0.0,
+        unlucky_design::inkcat::metrics::CHIP_PAD_X,
+    ]))
+    .style(chip_style(
+        ui,
+        selected,
+        content_color,
+        border_color,
+        stroke,
+        radius,
+    ))
+    .on_press(Message::Language(choice))
+    .into()
+}
+
+/// [`chip`] 的样式闭包（抽成自由函数：单测要**直接**喂 `Hovered` / `Pressed` 两态）。
+///
+/// - **α 只从 [`Interaction`] 来**：hover 8% / pressed 10%（M3）。M284 之前两种态合并成一条
+///   `matches!(status, Hovered | Pressed)` 分支、都叠 `StateLayer::Hover`，按下于是被压成 8%；
+/// - **合成底是 [`frame::BASE`]**（M237：这一组住在 `frame::card` 里，状态层叠卡底而不是画布）。
+fn chip_style<'a>(
+    ui: &'a Ui,
+    selected: bool,
+    content_color: Color,
+    border_color: Color,
+    stroke: f32,
+    radius: Radius,
+) -> impl Fn(&IcedTheme, button::Status) -> button::Style + 'a {
+    move |_theme, status| {
+        let background = if selected {
+            Some(Background::Color(ui.color(Role::SecondaryContainer)))
+        } else {
+            interaction::layer_color(
+                ui,
+                Interaction::from_status(status),
+                Role::OnSurface,
+                frame::BASE.role(),
+            )
+            .map(Background::Color)
+        };
+
+        button::Style {
+            background,
+            text_color: content_color,
+            border: Border {
+                color: border_color,
+                width: if selected { 0.0 } else { stroke },
+                radius,
+            },
+            shadow: Shadow::default(),
+            snap: true,
+        }
+    }
+}