[Bug] Monitor tool auto-triggers next turn on session resume, causing unexpected token usage

Bug Description
If monitor tool is not stopped and exiting claude with exit anyway, resuming the session that had monitor tool running when exit ocurred will auto trigger next turn, causing unexpected token usage. If session is very long (800k) and uses fable5 and cache miss, then that's a lot of unexpected cost.

Environment Info

• Platform: win32
• Terminal: null
• Version: 2.1.218
• Feedback ID: df3a1bab-6970-41a6-975c-91b015118262

Errors
Not really an error, claude-code simply auto started the turn in the resumed session. Which can lead to unexpected cost, especially the session is old and long and uses Fable 5. 800k token at cache miss rate is going to hurt.

● No completion record was found for this background shell command from the previous session. It may have been stopped (via the UI, Monitor timeout, or agent teardown — these leave no transcript marker), or it may have been running when the previous Claude Code process exited. Check the output file for partial results before assuming it completed.

The monitor stopped running (no completion record — likely killed by a timeout/teardown, not something you did). It only fired once. Let me know if you want it restarted for continued testing.

✻ Cooked for 2s