feat(debugger): Browse the debug console history and open diff settings from the keyboard (#162)

- Debug console: typed expressions are kept per project, and Browse Console
  History (⌥⌘E / Ctrl+Alt+E) lists them, most recent first, to put one back
  into the input.
- Diff viewer: Diff Settings (⇧⌘D / Ctrl+Shift+D) opens the viewer options
  (side-by-side / unified, whitespace, highlighting, collapsing, scroll sync)
  as a popup menu.

src/features/vcs/compare.tsx

@@ -125,6 +125,15 @@ export function registerCompareActions(): () => void {
       when: "diffEditorFocus",
       run: () => focusedDiffNavigator()?.prev(),
     },
+    {
+      id: "diff.showSettings",
+      title: "Diff Settings",
+      category: "Diff",
+      icon: "settings",
+      keywords: ["ignore whitespace", "highlighting", "side-by-side", "unified"],
+      when: "diffEditorFocus",
+      run: () => focusedDiffNavigator()?.showSettings(),
+    },
     {
       id: "diff.nextFile",
       title: "Compare Next File",