Add notification message storage and waiting session timeout handling

[amahpour]

Summary

This PR enhances the notification event handling and adds special timeout logic for sessions in the "waiting" state. Notification messages are now stored in task_description, and waiting sessions receive a longer stale timeout (10 minutes instead of 5 minutes) with prominent logging.

Key Changes

• Notification message storage: When a Notification event is received with a non-empty message field, it is now stored in the session's task_description. Empty or missing messages do not overwrite existing descriptions.

• Waiting session timeout handling: Sessions in "waiting" status now use a 10-minute stale timeout instead of the standard 5-minute timeout, allowing more time for operator approval. Non-waiting sessions continue to use the 5-minute threshold.

• Enhanced logging: When a waiting session times out, a warning is logged with the session ID and elapsed time to help operators identify sessions that have been pending approval for too long.

• Comprehensive test coverage: Added 15 new tests covering:

  • Notification message storage with various edge cases (empty message, missing field, auto-session creation)
  • Broadcast callback triggering on notification events
  • Full session lifecycle transitions (idle → working → waiting → working → idle)
  • Race conditions (rapid notifications, notification followed by immediate stop)
  • Stale checker behavior for waiting vs. non-waiting sessions
  • Warning log verification for long-waiting sessions

Implementation Details

• The notification handler checks for a non-empty message field before updating task_description, preventing accidental overwrites.
• The stale checker now branches on session status: waiting sessions check against a 600-second (10-minute) threshold with warning-level logging, while other statuses use the existing 300-second (5-minute) threshold.
• All new tests follow existing patterns and use mocking/patching to avoid side effects.

https://claude.ai/code/session_01KdGbmDksNwHqRcCj2TvdAy

[github-actions]

Unit Test Coverage

File	Stmts	Miss	Cover	Missing
__init__.py	0	0	100%
db.py	133	2	98%	131–132
hooks.py	147	2	98%	178, 181
main.py	37	0	100%
pr_lookup.py	113	2	98%	53–54
sessions.py	0	0	100%
terminal.py	98	0	100%
watcher.py	380	16	95%	25–28, 337, 528–529, 563–571
routes
__init__.py	0	0	100%
api.py	146	0	100%
ws.py	106	8	92%	64–65, 103–104, 106, 125, 141–142
TOTAL	1160	30	97%

Tests	Skipped	Failures	Errors	Time
269	0 💤	0 ❌	0 🔥	16.599s ⏱️