fix(settings): one control language down the right-hand column

The page had drifted from the design system: dropdowns and secondary
buttons were raised white with a drop shadow, fields had a half-pixel
inset ring that anti-aliased to nothing on a 1x display (the shell and
proxy rows read as loose monospace text), and dropdowns sized to their
value beside fixed-width fields, so the column's left edge zig-zagged.

Fields, dropdowns, secondary buttons, steppers and search fields now all
stand on the theme's muted well with no outline or shadow; a field shows
a ring only for focus (accent) or error. Fields and dropdowns are 28px
and one width (kit::CONTROL_W); only path and command fields are wider.
Field text is sized on the Input itself, since its own text_sm outranked
the size set around it. A host saved under its own address no longer
repeats it as a subtitle.

docs/design-system.md

@@ -101,7 +101,9 @@ Git 的新增/修改标记种子为绿 `#2F8A52` / `#4CC27A`、琥珀 `#B7791F`
   页标题立在 48px 标题栏带内；分组标题 28px、11.5/16rem medium 辅助色；分组之间是 0.5px 分隔线，上下各 16px。
   设置行：标签正文色 regular，描述 12/16rem 辅助色，行最低 28px、内边距 8（hover/搜索命中的底色外扩 8px）；
   搜索命中行用浅中性底，不用强调色。输入框与下拉框 28px，按钮、步进器 26px（圆角 6）；
-  输入框/下拉框/次要按钮都用同一浅底（surface 半阶）且无描边。控件一义一种：开关管开/关，下拉管单选
+  输入框/下拉框/次要按钮都用同一浅底（主题 `muted`，与对话框输入井、侧栏搜索同色）且无描边、无阴影；
+  输入框只在聚焦（强调色）或出错（红）时显示 1px 内环。右侧控件列统一 180px 宽（`kit::CONTROL_W`），
+  只有路径/命令类输入加宽到 240px；过长的值省略号截断。控件一义一种：开关管开/关，下拉管单选
   （不再用分段控件），滑块管连续值，步进器管整数微调。
   每个视图唯一的主操作（保存主题草稿、连接、安装更新）用反色中性，同 Git 提交按钮；不可执行时回到浅底。
   开关与滑块仍用强调色。SSH 主机列表：标题行带 26px 图标按钮，28px 浅底搜索，分组标题 22px，
@@ -126,7 +128,8 @@ Git 的新增/修改标记种子为绿 `#2F8A52` / `#4CC27A`、琥珀 `#B7791F`
 - **SFTP 浏览器**：行与本地文件树一致（26px、圆角 6、16px 图标辅助色、文件名侧栏标题色、大小等宽数字）；
   编辑框为无边框淡底井（圆角 7）；传输进度为正文色细条压在淡底轨道上，失败才转红。
 - **面板里的主按钮**（SFTP 确认、添加转发、SSH 断线条的重连）：反色中性，同对话框主按钮。
-- **对话框**（SSH 认证/主机密钥、新建 worktree）：`ui::dialog` 统一外壳，同切换器的 12px 圆角、
+- **对话框**（SSH 认证/主机密钥、新建 worktree，以及所有确认框——关闭标签、退出、丢弃更改、删除文件等 `window.prompt`，
+  三个平台都不用系统原生弹窗）：`ui::dialog` 统一外壳，同切换器的 12px 圆角、
   浮层阴影与遮罩、距顶 112px；标题行 48px（正文字号 medium，右侧 `esc` 键帽，下接细线），
   内容区左右 18px、字段间距 14px；字段名 11.5/16rem medium 辅助色，输入框为无边框 28px
   淡底井（`muted`、圆角 7）。页脚 40px 细线分隔，按钮 28px / 圆角 6、右对齐、主操作在最右：
@@ -134,6 +137,9 @@ Git 的新增/修改标记种子为绿 `#2F8A52` / `#4CC27A`、琥珀 `#B7791F`
   退回淡底 + 辅助色且不响应点击。主机名与指纹放在淡底信息井里用等宽字。唯一的红色按钮是
   「主机密钥已变更」的 Override，该卡片也是唯一带红色描边的对话框。
 - **浮动提示条**：边缘保持中性细线，严重程度只由行首 6px 状态点表达（警告琥珀、断开红）。
+  文档栏里的「文件已在磁盘上更改」横条同理：中性底 + 底部细线 + 琥珀点，按钮用对话框按钮，安全的「保留我的」为主。
+- **通知（toast）**：出错时带标题说明哪个操作失败（如「git push 失败」），原因作为次级文字，带状态图标；
+  不直接把一行 stderr 当作全部内容。设置窗口是独立窗口，同样要渲染通知层。
 - **首页**：快捷操作列表 340px 宽，行高 28px、圆角 7，静止无底、hover 取窗口 hover 阶；
   快捷键用 18px 淡底键帽。
 - **终端**：ANSI 是用户内容，不拿来充当 UI 错误/成功配色；应用设计调整不得反转状态含义。

src/ui/settings.rs

@@ -88,8 +88,13 @@ fn ui_scale(cx: &App) -> f32 {
     cx.global::<Config>().ui_font_size / UI_FONT_SIZE_DEFAULT
 }
 
-/// How wide a text field in the right-hand column is.
-const FIELD_W: f32 = 180.;
+/// How wide a text field in the right-hand column is — the dropdowns' width,
+/// so the column is one straight edge whichever control a row holds.
+const FIELD_W: f32 = crate::ui::settings::kit::CONTROL_W;
+
+/// A field for a path or a command line: the one kind of value unreadable cut
+/// short, so the one kind allowed past [`FIELD_W`].
+const PATH_FIELD_W: f32 = 240.;
 
 /// The host editor's label column, and how wide a field beside one grows to.
 const SSH_LABEL_W: f32 = 96.;

src/ui/settings/hosts.rs

@@ -419,6 +419,11 @@ impl Tty7App {
             (false, None) => (t(L10nKey::SettingsNewHost).to_string(), String::new()),
         };
         let blank_title = editing && p.is_none() && title == t(L10nKey::SettingsNewHost);
+        // A host saved under its own address is titled with that address, and
+        // a second line saying it again is noise — the rule the New Tab menu
+        // already keeps. While editing, the line is the form's live preview
+        // and stays.
+        let echo = !editing && address == title;
         let (meta, meta_color) = if dirty {
             (t(L10nKey::SettingsUnsaved).to_string(), tk.warn_text)
         } else if live {
@@ -463,15 +468,17 @@ impl Tty7App {
                             .text_color(if blank_title { tk.k4 } else { tk.fg })
                             .child(title),
                     )
-                    .child(
-                        div()
-                            .font_family(Tk::mono(cx))
-                            .text_size(fs(11.))
-                            .line_height(px(15.))
-                            .text_color(tk.k45)
-                            .truncate()
-                            .child(address),
-                    ),
+                    .when(!echo, |col| {
+                        col.child(
+                            div()
+                                .font_family(Tk::mono(cx))
+                                .text_size(fs(11.))
+                                .line_height(px(15.))
+                                .text_color(tk.k45)
+                                .truncate()
+                                .child(address),
+                        )
+                    }),
             )
             .child(
                 div()

src/ui/settings/kit.rs

@@ -49,6 +49,15 @@ pub(crate) struct Tk {
     pub nav: Hsla,
     /// A raised button's fill.
     pub btn: Hsla,
+    /// The one fill every control on the page stands on — field, dropdown,
+    /// secondary button, stepper — the theme's `muted`, the same well the
+    /// dialogs' fields and the sidebar's search sit in. No outline, no drop.
+    pub well: Hsla,
+    /// [`Self::well`] a step firmer, under the pointer or while open.
+    pub well_hover: Hsla,
+    /// The focus ring: the accent, the one colour kept for "the keyboard
+    /// is here".
+    pub focus: Hsla,
     /// A popover's fill.
     pub menu: Hsla,
     /// A switch or slider knob at rest.
@@ -76,6 +85,7 @@ impl Tk {
         let page = theme.background;
         let a = |light: f32, dark_a: f32| fg.opacity(if dark { dark_a } else { light });
         let white = gpui::white();
+        let well = theme.muted;
         Self {
             dark,
             fg,
@@ -95,6 +105,9 @@ impl Tk {
             heading: a(0.9, 0.9),
             nav: a(0.82, 0.8),
             btn: if dark { fg.opacity(0.1) } else { white },
+            well,
+            well_hover: well.blend(fg.opacity(if dark { 0.06 } else { 0.05 })),
+            focus: theme.ring,
             menu: if dark { lift(page, 0.06) } else { white },
             knob: if dark { fg } else { white },
             chip: if dark { fg.opacity(0.16) } else { white },
@@ -330,13 +343,12 @@ impl RenderOnce for Btn {
                 .px(px(12.))
                 .when(self.icon.is_some(), |b| b.pl(px(9.)).pr(px(11.)))
                 .rounded(px(6.))
-                .bg(tk.btn)
-                .shadow(tk.raised())
+                .bg(tk.well)
                 .text_size(self.size.unwrap_or(fs(12.5)))
                 .text_color(tk.fg)
                 .when(!self.disabled, |b| {
-                    b.hover(move |s| s.shadow(tk.raised_hover()))
-                        .active(move |s| s.bg(tk.k05))
+                    b.hover(move |s| s.bg(tk.well_hover))
+                        .active(move |s| s.bg(tk.well_hover.blend(tk.k05)))
                 }),
             BtnKind::Primary => base
                 .h(px(26.))
@@ -409,22 +421,31 @@ pub(crate) fn search_glass(size: f32, tk: &Tk) -> Icon {
         .text_color(tk.k35)
 }
 
+/// The height of a field or a dropdown. Buttons and steppers are a step
+/// lower, at 26.
+pub(crate) const CONTROL_H: f32 = 28.;
+
 /// A search field with a hairline ring, for filtering a list on the page.
 pub(crate) fn search_field(input: &gpui::Entity<InputState>, tk: &Tk) -> Div {
     h_flex()
-        .h(px(26.))
+        .h(px(CONTROL_H))
         .px(px(8.))
         .gap(px(6.))
         .items_center()
-        .rounded(px(6.))
-        .shadow(vec![ring(tk.k15, 0.5, true)])
+        .rounded(px(7.))
+        .bg(tk.well)
         .child(search_glass(10., tk))
         .child(
-            div()
-                .flex_1()
-                .min_w_0()
-                .text_size(fs(12.5))
-                .child(Input::new(input).appearance(false).px_0().py_0().h(px(24.))),
+            // On the input, not around it: `Input` sets its own `text_sm`
+            // and only a size given to it directly outranks that.
+            div().flex_1().min_w_0().child(
+                Input::new(input)
+                    .appearance(false)
+                    .px_0()
+                    .py_0()
+                    .h(px(24.))
+                    .text_size(fs(12.5)),
+            ),
         )
 }
 
@@ -437,32 +458,36 @@ pub(crate) fn text_field(
     tk: &Tk,
     cx: &App,
 ) -> Div {
-    let ring_color = if invalid {
-        tk.danger
-    } else if focused {
-        tk.k45
-    } else {
-        tk.k15
+    // At rest a field is only its well. The ring is kept for the two states
+    // that have to be seen at a glance: where the keyboard is, and what is
+    // wrong.
+    let ring_color = match (invalid, focused) {
+        (true, _) => Some(tk.danger),
+        (false, true) => Some(tk.focus),
+        (false, false) => None,
     };
     div()
-        .h(px(26.))
+        .h(px(CONTROL_H))
         .px(px(10.))
         .flex()
         .items_center()
         .rounded(px(6.))
-        .shadow(vec![ring(
-            ring_color,
-            if focused || invalid { 1. } else { 0.5 },
-            true,
-        )])
+        .bg(tk.well)
+        .when_some(ring_color, |f, c| f.shadow(vec![ring(c, 1., true)]))
         .font_family(Tk::mono(cx))
-        .text_size(fs(12.))
         .text_color(tk.fg)
         .child(
-            div()
-                .flex_1()
-                .min_w_0()
-                .child(Input::new(input).appearance(false).px_0().py_0().h(px(24.))),
+            div().flex_1().min_w_0().child(
+                Input::new(input)
+                    .appearance(false)
+                    .px_0()
+                    .py_0()
+                    .h(px(24.))
+                    // The input's own `text_sm` beat the 12px set on this
+                    // box, so the value stood a size above every dropdown
+                    // label in the same column.
+                    .text_size(fs(12.)),
+            ),
         )
 }
 
@@ -489,8 +514,16 @@ pub(crate) fn section_head(title: &str, desc: Option<String>, tk: &Tk) -> Div {
         })
 }
 
+/// The width of a control in the page's right-hand column — dropdown or text
+/// field alike. The column used to size each dropdown to its value (anything
+/// from 148 to 260) beside fields fixed at 180, so its left edge zig-zagged
+/// down the page. One width, and a value too long for it elides. Only fields
+/// that hold a path or a command line are wider, because those are unreadable
+/// cut short.
+pub(crate) const CONTROL_W: f32 = 180.;
+
 /// The trigger of a dropdown: a raised button with the current value, an
-/// optional mark before it, and a chevron.
+/// optional mark before it, and a chevron, [`CONTROL_W`] wide.
 pub(crate) fn select_trigger(
     id: impl Into<ElementId>,
     label: impl Into<SharedString>,
@@ -500,17 +533,16 @@ pub(crate) fn select_trigger(
 ) -> Stateful<Div> {
     h_flex()
         .id(id)
-        .h(px(26.))
-        .min_w(px(148.))
-        .max_w(px(260.))
+        .h(px(CONTROL_H))
+        .w(px(CONTROL_W))
+        .flex_shrink_0()
         .pl(px(if leading.is_some() { 8. } else { 10. }))
         .pr(px(7.))
         .gap(px(8.))
         .items_center()
         .rounded(px(6.))
-        .bg(if open { tk.k05 } else { tk.btn })
-        .shadow(tk.raised())
-        .hover(move |s| s.shadow(tk.raised_hover()))
+        .bg(if open { tk.well_hover } else { tk.well })
+        .hover(move |s| s.bg(tk.well_hover))
         .cursor_pointer()
         .text_size(fs(12.5))
         .text_color(tk.fg)
@@ -642,7 +674,9 @@ pub(crate) fn stepper(
             .text_color(tk.k6)
             .when(!enabled, |d| d.opacity(0.35))
             .when(enabled, |d| {
-                d.cursor_pointer().active(move |s| s.bg(tk.k05))
+                d.cursor_pointer()
+                    .hover(move |s| s.bg(tk.well_hover))
+                    .active(move |s| s.bg(tk.well_hover.blend(tk.k05)))
             })
             .child(glyph)
     };
@@ -652,8 +686,7 @@ pub(crate) fn stepper(
         .h(px(26.))
         .items_center()
         .rounded(px(6.))
-        .bg(tk.btn)
-        .shadow(tk.raised())
+        .bg(tk.well)
         .child(
             end("dec", "−", s.can_dec)
                 .rounded_l(px(6.))

src/ui/settings/pages.rs

@@ -756,7 +756,10 @@ impl Tty7App {
                 .id("shell-program-detected-trigger")
                 .flex_shrink_0()
                 .ml(px(4.))
-                .mr(px(-4.))
+                // Pulled into the field's 10px padding far enough that the
+                // chevron's centre sits 12px from the edge — where a
+                // dropdown's does, one row down.
+                .mr(px(-7.))
                 .size(px(18.))
                 .rounded(px(4.))
                 .flex()
@@ -849,7 +852,7 @@ impl Tty7App {
             let value = wd_path_input.read(cx).value();
             let error = (!crate::ui::app::wd_path_saveable(&value))
                 .then(|| t(L10nKey::SettingsWdPathInvalid).to_string());
-            let control = self.settings_checked_input(&wd_path_input, 240., error, cx);
+            let control = self.settings_checked_input(&wd_path_input, PATH_FIELD_W, error, cx);
             rows.push(
                 self.settings_row(
                     t(L10nKey::SettingsCustomPath),
@@ -936,7 +939,7 @@ impl Tty7App {
         // reads as "this is what file links do".
         let link_file_command_row = (link_file_open == LinkFileOpen::Command).then(|| {
             let control = self
-                .settings_text_input(&link_file_command_input, 240., false, cx)
+                .settings_text_input(&link_file_command_input, PATH_FIELD_W, false, cx)
                 .into_any_element();
             self.settings_row(
                 t(L10nKey::SettingsOpenFilesCommand),

src/ui/settings/shell.rs

@@ -143,7 +143,8 @@ impl Tty7App {
                 d.child(kit::popover_below(
                     true,
                     4.,
-                    self.settings_menu_panel(&id, entries, cx).min_w(px(148.)),
+                    self.settings_menu_panel(&id, entries, cx)
+                        .min_w(px(kit::CONTROL_W)),
                 ))
             })
             .into_any_element()