- Release reservation on service change, date change, and step-back navigation
- Add synchronous double-click payment guard (isProcessingPaymentSync)
- Immutable update for confirmedBooking to prevent race-condition overcharge
- Generate fresh idempotency key per submission attempt (was reused across
component lifetime, causing stale-booking illusion on re-submit)
- Release reservation after successful booking submission
- Extract releaseReservation() helper for DRY reservation cleanup
- Race-condition guard in selectTimeWithValidation: pass clicked time
explicitly so stale validation can't clobber a newer selection
popertots
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