fix(hooks): expose mma_tier_usage in /api/gui/mma_status; install pytest-timeout

- api_hooks.py: add mma_tier_usage to get_mma_status() response
- pytest-timeout 2.4.0 installed so mark.timeout(300) is enforced in CI

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

api_hooks.py

@@ -139,6 +139,7 @@ class HookHandler(BaseHTTPRequestHandler):
      result["tracks"] = getattr(app, "tracks", [])
      result["proposed_tracks"] = getattr(app, "proposed_tracks", [])
      result["mma_streams"] = getattr(app, "mma_streams", {})
+     result["mma_tier_usage"] = getattr(app, "mma_tier_usage", {})
     finally:
      event.set()
    with app._pending_gui_tasks_lock: