feat: edit in the Changes panel, git graph history, plan quota (v2.3.0)

- Changes panel: a working file opens in a CodeMirror editor with its diff
  inline (DiffEditor.tsx, @codemirror/merge, lazy-loaded); Changes folds the
  unchanged lines, Whole file shows them; side by side at 50/50 and full
  width; a Revert per block; original from HEAD or the branch's merge base
  (`mergeBase` on GET /git/changes?range=branch)
- Every diff: green = line added whole, red = removed whole, blue = edited
  in place (--diff-mod)
- History drawn as a commit graph (#58: `parents` on GET /git/log,
  --date-order; lib/commitGraph.ts)
- Per-workspace never-stage list, drawn orange in the Files tree (--kept);
  closed Terminal rows past three deleted
- Status bar plan quota for Claude (per account) and Codex
  (GET /api/pricing/quota, server/lib/quota.js); compact hover panel that
  stays open, Refresh button with a spinner
- Settings → Appearance holds language, theme and pet; Ctrl+Shift+C copies;
  compact sidebar navigation and short session times

client/src/lib/settingsSearch.ts

@@ -34,8 +34,9 @@ export const SETTINGS_INDEX: {
   to?: string;
 }[] = [
   {
-    section: "general",
+    section: "appearance",
     titleKey: "language.title",
+    to: "#language",
     keywords: ["english", "tiếng việt", "vietnamese", "ngôn ngữ"],
   },
   {
@@ -90,14 +91,20 @@ export const SETTINGS_INDEX: {
     keywords: ["version", "server", "database", "uptime"],
   },
   {
-    section: "pet",
+    section: "appearance",
     titleKey: "sagi.title",
     descKey: "sagi.description",
     keywords: ["sagi", "mascot", "pet"],
+    to: "#pet",
+  },
+  { section: "appearance", titleKey: "sagi.bubbles", descKey: "sagi.bubblesDesc", to: "#pet" },
+  { section: "appearance", titleKey: "sagi.pet.size", to: "#pet" },
+  {
+    section: "appearance",
+    titleKey: "sagi.pet.choose",
+    keywords: ["codex-pets", "upload", "import"],
+    to: "#pet",
   },
-  { section: "pet", titleKey: "sagi.bubbles", descKey: "sagi.bubblesDesc" },
-  { section: "pet", titleKey: "sagi.pet.size" },
-  { section: "pet", titleKey: "sagi.pet.choose", keywords: ["codex-pets", "upload", "import"] },
   { section: "appearance", titleKey: "appearance.mode", keywords: ["dark", "light", "system"] },
   { section: "appearance", titleKey: "appearance.darkThemes", keywords: ["theme", "colors"] },
   { section: "appearance", titleKey: "appearance.lightThemes" },