feat: add user-configurable theme settings

crates/ui/src/form.rs

@@ -1,4 +1,5 @@
 use gpui::{App, Div, IntoElement, ParentElement, SharedString, Styled, div};
+use gpui_kit::base::StyledExt as _;
 use gpui_kit::component::{ActiveTheme, h_flex, v_flex};
 
 /// A settings row: the label and description on the left, the control on the right.
@@ -9,14 +10,15 @@ pub fn settings_row(
     cx: &App,
 ) -> Div {
     h_flex()
-        .gap_3()
+        .w_full()
+        .gap_4()
         .items_center()
         .justify_between()
         .child(
             v_flex()
                 .flex_1()
                 .min_w_0()
-                .child(div().text_sm().child(label.into()))
+                .child(div().text_sm().font_semibold().child(label.into()))
                 .child(
                     div()
                         .text_xs()
@@ -24,5 +26,37 @@ pub fn settings_row(
                         .child(description.into()),
                 ),
         )
+        .child(
+            h_flex()
+                .w_40()
+                .flex_shrink_0()
+                .justify_end()
+                .items_center()
+                .child(control),
+        )
+}
+
+/// A full-width settings block with the label and description in one header.
+pub fn settings_block(
+    label: impl Into<SharedString>,
+    description: impl Into<SharedString>,
+    control: impl IntoElement,
+    cx: &App,
+) -> impl IntoElement {
+    v_flex()
+        .w_full()
+        .gap_3()
+        .child(
+            v_flex()
+                .w_full()
+                .child(div().text_sm().font_semibold().child(label.into()))
+                .child(
+                    div()
+                        .text_xs()
+                        .text_color(cx.theme().muted_foreground)
+                        .truncate()
+                        .child(description.into()),
+                ),
+        )
         .child(control)
 }