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__/tmux.test.js

@@ -57,6 +57,53 @@ describe("tmux wrapper", () => {
     assert.equal(tmux.liveSessions(), null);
   });
 
+  describe(
+    "the tmux server outlives the dashboard (Linux)",
+    { skip: process.platform !== "linux" },
+    () => {
+      // Fake tmux: no server until a new-session, then every call succeeds.
+      const fake =
+        (calls, { running = false } = {}) =>
+        (args) => {
+          calls.push(["tmux", ...args].join(" "));
+          if (args[0] === "display-message" && !running)
+            throw Object.assign(new Error("no server"), { status: 1 });
+          if (args[0] === "has-session" && !running)
+            throw Object.assign(new Error("no session"), { status: 1 });
+          return args[0] === "display-message" ? "4242\n" : "";
+        };
+
+      it("starts the FIRST session in its own systemd scope, not the dashboard's cgroup", () => {
+        const calls = [];
+        tmux.__setExecImpl(fake(calls));
+        tmux.__setScopeImpl((args) => calls.push(["systemd-run", "tmux", ...args].join(" ")));
+        tmux.newSession({ name: "agenthub-lane-1", cwd: "/w", argv: ["claude"], env: {} });
+        assert.ok(
+          calls.includes("systemd-run tmux new-session -d -s agenthub-lane-1 -c /w -- claude")
+        );
+        assert.ok(!calls.some((c) => c.startsWith("tmux new-session")));
+      });
+
+      it("adds a session to a running server directly", () => {
+        const calls = [];
+        tmux.__setExecImpl(fake(calls, { running: true }));
+        tmux.__setScopeImpl(() => assert.fail("a running server needs no scope"));
+        tmux.newSession({ name: "agenthub-lane-1", cwd: "/w", argv: ["claude"], env: {} });
+        assert.ok(calls.includes("tmux new-session -d -s agenthub-lane-1 -c /w -- claude"));
+      });
+
+      it("starts it plainly when no systemd user manager answers", () => {
+        const calls = [];
+        tmux.__setExecImpl(fake(calls));
+        tmux.__setScopeImpl(() => {
+          throw Object.assign(new Error("Failed to connect to bus"), { status: 1 });
+        });
+        tmux.newSession({ name: "agenthub-lane-1", cwd: "/w", argv: ["claude"], env: {} });
+        assert.ok(calls.includes("tmux new-session -d -s agenthub-lane-1 -c /w -- claude"));
+      });
+    }
+  );
+
   it("newSession names a command that exited at once instead of tmux's set-option error", () => {
     tmux.__setExecImpl((args) => {
       if (args[0] === "new-session") return "";