EventFlow // Cancellation Propagation
Transactional Outbox Pattern & Async Queue Execution
STEP 1/6: USER CANCEL ACTION User initiates cancellation request via API.
DATABASE TRANSACTION BOUNDARY (ATOMIC) HTTP POST INVOKE AUDIT LOG INSERT TX STAGING CDC / POLL PUBLISH DISPATCH USER CANCEL ACTION REGISTRATION SERVICE WAITLIST SERVICE AUDIT LOG ENTRY OUTBOX TABLE WORKER NOTIFICATION QUEUE NEXT ATTENDEE PROMOTED