When AI flags an event, transition status to 'flagged' instead of
leaving it as 'pending'. This prevents processPending() from picking
up the same flagged events every 30-second poll cycle and burning
AI tokens indefinitely.
- Add 'flagged' to QUEUE_STATUSES enum in schema
- Set status='flagged' in autoReview() when AI flags an event
- Include flagged count in admin stats endpoint
- Add index on relay_event_queue.status for efficient queries
Fixes#27
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
