refactor(tui): extract shared setting edit overlay (#1776)

The draw_edit_overlay function in sandbox_settings and global_settings
was nearly identical — the only difference was which settings slice the
entry was resolved from (app.sandbox_settings vs app.global_settings).

Extract the common rendering logic into draw_setting_edit_overlay in
ui/mod.rs, taking key/kind/edit/area/theme as parameters. Each pane
now resolves its own entry and delegates to the single implementation.

Net: -75 lines, +61 lines across the three files.

crates/openshell-tui/src/ui/global_settings.rs

@@ -120,46 +120,10 @@ fn draw_edit_overlay(
     edit: &crate::app::SettingEditState,
     area: Rect,
 ) {
-    let t = &app.theme;
     let Some(entry) = app.global_settings.get(edit.index) else {
         return;
     };
-
-    let title = format!(" Edit: {} ({}) ", entry.key, entry.kind.as_str());
-    let mut lines = vec![
-        Line::from(Span::styled(&title, t.heading)),
-        Line::from(""),
-        Line::from(vec![
-            Span::styled("Value: ", t.muted),
-            Span::styled(&edit.input, t.text),
-            Span::styled("_", t.accent),
-        ]),
-    ];
-
-    if let Some(ref err) = edit.error {
-        lines.push(Line::from(""));
-        lines.push(Line::from(Span::styled(err, t.status_err)));
-    }
-
-    lines.push(Line::from(""));
-    lines.push(Line::from(vec![
-        Span::styled("[Enter]", t.key_hint),
-        Span::styled(" Confirm  ", t.muted),
-        Span::styled("[Esc]", t.key_hint),
-        Span::styled(" Cancel", t.muted),
-    ]));
-
-    // content lines + 2 for border
-    let popup_height = u16::try_from(lines.len() + 2).unwrap_or(u16::MAX);
-    let popup = centered_rect(50, popup_height, area);
-    frame.render_widget(Clear, popup);
-
-    let block = Block::default()
-        .borders(Borders::ALL)
-        .border_style(t.border_focused)
-        .padding(Padding::horizontal(1));
-
-    frame.render_widget(Paragraph::new(lines).block(block), popup);
+    super::draw_setting_edit_overlay(frame, &entry.key, entry.kind, edit, area, &app.theme);
 }
 
 fn draw_confirm_set(frame: &mut Frame<'_>, app: &App, idx: usize, area: Rect) {

crates/openshell-tui/src/ui/mod.rs

@@ -18,9 +18,10 @@ use ratatui::Frame;
 use ratatui::layout::{Constraint, Direction, Layout, Rect};
 use ratatui::style::Style;
 use ratatui::text::{Line, Span};
-use ratatui::widgets::{Block, Borders, Paragraph};
+use ratatui::widgets::{Block, Borders, Clear, Padding, Paragraph};
 
-use crate::app::{self, App, Focus, InputMode, Screen};
+use crate::app::{self, App, Focus, InputMode, Screen, SettingEditState};
+use crate::theme::Theme;
 
 pub fn draw(frame: &mut Frame<'_>, app: &mut App) {
     // Splash screen is a full-screen takeover — no chrome.
@@ -512,6 +513,62 @@ pub fn centered_rect(width: u16, height: u16, area: Rect) -> Rect {
     horiz[1]
 }
 
+// ---------------------------------------------------------------------------
+// Shared setting-edit overlay (used by both global and sandbox settings panes)
+// ---------------------------------------------------------------------------
+
+/// Render the generic setting-edit text-input overlay.
+///
+/// Both the global-settings and sandbox-settings panes show the same editor
+/// overlay — an input box with the setting key/type in the title, an error
+/// line when validation fails, and `[Enter]`/`[Esc]` hints.  This function
+/// is the single implementation; each pane resolves its own entry and then
+/// delegates here.
+fn draw_setting_edit_overlay(
+    frame: &mut Frame<'_>,
+    key: &str,
+    kind: openshell_core::settings::SettingValueKind,
+    edit: &SettingEditState,
+    area: Rect,
+    theme: &Theme,
+) {
+    let t = theme;
+    let title = format!(" Edit: {} ({}) ", key, kind.as_str());
+    let mut lines = vec![
+        Line::from(Span::styled(&title, t.heading)),
+        Line::from(""),
+        Line::from(vec![
+            Span::styled("Value: ", t.muted),
+            Span::styled(&edit.input, t.text),
+            Span::styled("_", t.accent),
+        ]),
+    ];
+
+    if let Some(ref err) = edit.error {
+        lines.push(Line::from(""));
+        lines.push(Line::from(Span::styled(err.as_str(), t.status_err)));
+    }
+
+    lines.push(Line::from(""));
+    lines.push(Line::from(vec![
+        Span::styled("[Enter]", t.key_hint),
+        Span::styled(" Confirm  ", t.muted),
+        Span::styled("[Esc]", t.key_hint),
+        Span::styled(" Cancel", t.muted),
+    ]));
+
+    let popup_height = u16::try_from(lines.len() + 2).unwrap_or(u16::MAX);
+    let popup = centered_popup(50, popup_height, area);
+    frame.render_widget(Clear, popup);
+
+    let block = Block::default()
+        .borders(Borders::ALL)
+        .border_style(t.border_focused)
+        .padding(Padding::horizontal(1));
+
+    frame.render_widget(Paragraph::new(lines).block(block), popup);
+}
+
 /// Center a popup rectangle within `area` using percentage-based width and
 /// an absolute height (in rows).
 pub fn centered_popup(percent_x: u16, height: u16, area: Rect) -> Rect {

crates/openshell-tui/src/ui/sandbox_settings.rs

@@ -128,45 +128,10 @@ fn draw_edit_overlay(
     edit: &crate::app::SettingEditState,
     area: Rect,
 ) {
-    let t = &app.theme;
     let Some(entry) = app.sandbox_settings.get(edit.index) else {
         return;
     };
-
-    let title = format!(" Edit: {} ({}) ", entry.key, entry.kind.as_str());
-    let mut lines = vec![
-        Line::from(Span::styled(&title, t.heading)),
-        Line::from(""),
-        Line::from(vec![
-            Span::styled("Value: ", t.muted),
-            Span::styled(&edit.input, t.text),
-            Span::styled("_", t.accent),
-        ]),
-    ];
-
-    if let Some(ref err) = edit.error {
-        lines.push(Line::from(""));
-        lines.push(Line::from(Span::styled(err, t.status_err)));
-    }
-
-    lines.push(Line::from(""));
-    lines.push(Line::from(vec![
-        Span::styled("[Enter]", t.key_hint),
-        Span::styled(" Confirm  ", t.muted),
-        Span::styled("[Esc]", t.key_hint),
-        Span::styled(" Cancel", t.muted),
-    ]));
-
-    let popup_height = u16::try_from(lines.len() + 2).unwrap_or(u16::MAX);
-    let popup = centered_rect(50, popup_height, area);
-    frame.render_widget(Clear, popup);
-
-    let block = Block::default()
-        .borders(Borders::ALL)
-        .border_style(t.border_focused)
-        .padding(Padding::horizontal(1));
-
-    frame.render_widget(Paragraph::new(lines).block(block), popup);
+    super::draw_setting_edit_overlay(frame, &entry.key, entry.kind, edit, area, &app.theme);
 }
 
 fn draw_confirm_set(frame: &mut Frame<'_>, app: &App, idx: usize, area: Rect) {