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.

server/__tests__/plugin-bootstrap.test.js

@@ -205,6 +205,37 @@ describe("fast path", () => {
   });
 });
 
+describe("fast path after a Quit (issue #65)", () => {
+  beforeEach(resetRuntime);
+
+  it("starts nothing while the stopped flag is set, and starts again once it is gone", () => {
+    const pkg = require("../../package.json");
+    const { markQuit, clearQuit } = require("../lib/quit");
+    const prevHome = process.env.HOME;
+    process.env.HOME = TMP_HOME; // the real unit may name another root: stale
+    try {
+      fs.mkdirSync(path.join(RT, "node_modules"), { recursive: true });
+      boot.writeState(
+        {
+          pluginVersion: pkg.version,
+          depsHash: boot.depsHash(),
+          pluginRoot: path.resolve(__dirname, "..", ".."),
+        },
+        RT
+      );
+      // No server is live: without the flag the worker would start one.
+      assert.equal(boot.fastPathOk(RT), false);
+      markQuit(RT);
+      assert.equal(boot.fastPathOk(RT), true);
+      clearQuit(RT);
+      assert.equal(boot.fastPathOk(RT), false);
+    } finally {
+      if (prevHome === undefined) delete process.env.HOME;
+      else process.env.HOME = prevHome;
+    }
+  });
+});
+
 describe("bootstrap lock", () => {
   beforeEach(resetRuntime);