perf: optimize event loop lock contention

[shenald-dev]

• Replaced getattr(self, 'is_shutting_down', False) with direct attribute access.
• Moved last_event_time and last_event_path assignments outside the lock in on_any_event.
• Implemented double-checked locking for spawning the debounce thread.
• Recorded learning to .jules/bolt.md.

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PR created automatically by Jules for task 10487350594901597601 started by @shenald-dev

[google-labs-jules]

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[shenald-dev]

The changes look solid for reducing lock contention. Ensure the double-checked locking pattern in the debounce thread spawn is safe (e.g., use a lock or threading.local to avoid race conditions on Python's GIL). Otherwise, ready to merge.

Reviewed — quality: high

[shenald-dev]

Looks good, merging this in. CI is green and everything checks out 👍

Optimizes event loop lock contention by using direct attribute access, moving assignments out of locks, and adding double-checked locking for debounce thread spawning.

[google-labs-jules]

The changes look solid for reducing lock contention. Ensure the double-checked locking pattern in the debounce thread spawn is safe (e.g., use a lock or threading.local to avoid race conditions on Python's GIL). Otherwise, ready to merge.

Reviewed — quality: high

The double-checked locking is protected by self.timer_lock inside the first check, which ensures it is safe and avoids race conditions.

[google-labs-jules]

Looks good, merging this in. CI is green and everything checks out 👍

Optimizes event loop lock contention by using direct attribute access, moving assignments out of locks, and adding double-checked locking for debounce thread spawning.

Acknowledged. Thanks for the review!