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/systemd-service.js

@@ -127,6 +127,12 @@ function unitIsActive(name) {
   return String(res.stdout || "").trim() === "active";
 }
 
+/** `KillMode=process`: a stop or an update's restart ends the server alone.
+ *  tmux forks its server from whichever process first asks for a session —
+ *  the dashboard itself, after a boot with autostart on — so it can sit in
+ *  this unit's cgroup, and the default `control-group` would kill it and every
+ *  lane pane with it. Panes close only on Quit (`server/lib/quit.js`), which
+ *  kills them itself. The launchd twin is `AbandonProcessGroup`. */
 function unitContent({ description, workingDir, execStart, env }) {
   const envLines = Object.entries(env)
     .map(([k, v]) => `Environment=${k}=${v}`)
@@ -142,6 +148,7 @@ WorkingDirectory=${workingDir}
 ExecStart=${execStart}
 Restart=always
 RestartSec=3
+KillMode=process
 ${envLines}
 
 [Install]