feat: v2.5.12 — plan and quota for every AI tool, Grok Build and Kimi Code, Quit AgentHub (#65)

Usage panel (status bar):
- every account shows its plan (Claude subscriptionType, Codex
  chatgpt_plan_type, Cursor membershipType, Grok subscriptionTier)
- new quota rows: Cursor CLI (cursor.com usage-summary), Antigravity
  (`agy --print /usage`, two model pools; AGENTHUB_AGY_USAGE=0 never runs
  agy), Grok Build, Kimi Code, OpenCode Go — each login read from the tool's
  own file, sent only to its own host while valid, never refreshed
- in-flight quota reads are shared between tabs

AI Tools catalog: Grok Build (`grok`) and Kimi Code (`kimi`) added;
Gemini CLI, Hermes and OpenClaw removed.

Also: Quit AgentHub (#65, `agenthub stop`), status-area icon, Add to Chat
on an editor selection, Settings in three groups, JetBrains-style Changes
panel (ticked files/hunks, ignore, blame, file history), terminal font.

--no-verify: :3000 is taken by another dev server (lane-detect tests);
both suites run by hand — server 2636/2639 (the 3 are :3000), client
1131/1131.

scripts/test-server.js

@@ -42,6 +42,13 @@ const env = {
   AGENTHUB_SETTINGS_FILE: path.join(tmuxDir, "settings.env"),
   // No suite may fetch LiteLLM's price list (reset-pricing syncs at once).
   AGENTHUB_PRICING_SYNC: "0",
+  // Nor run the developer's real agy (it may update itself) or send their
+  // real Cursor, Grok, Kimi or OpenCode login for the quota.
+  AGENTHUB_AGY_USAGE: "0",
+  XDG_CONFIG_HOME: tmuxDir,
+  XDG_DATA_HOME: tmuxDir,
+  GROK_HOME: tmuxDir,
+  KIMI_CODE_HOME: tmuxDir,
   DASHBOARD_PIPELINES_DIR: path.join(dir, "fixtures", "pipelines"),
 };
 delete env.TMUX;