Adds comprehensive push notification reminders using pg_cron + pg_net:
- Shift check-in reminder (15 min before, with countdown banner)
- Shift check-out reminder (hourly, persistent until checkout)
- Overtime idle reminder (15 min without task)
- Overtime checkout reminder (30 min after task completion)
- IT service request event reminder (1 hour before event)
- IT service request evidence reminder (daily)
- Paused task reminder (daily)
- Backlog reminder (15 min before shift end)
- Pass slip expiry reminder (15 min before 1-hour limit, with countdown banner)
Database: Extended scheduled_notifications table to support polymorphic references
(schedule_id, task_id, it_service_request_id, pass_slip_id) with unique constraint
and epoch column for deduplication. Implemented 8 enqueue functions + master dispatcher.
Uses pg_cron every minute to enqueue and pg_net to trigger process_scheduled_notifications
edge function, eliminating need for external cron job. Credentials stored in vault with
GUC fallback for flexibility.
Flutter: Added ShiftCountdownBanner and PassSlipCountdownBanner widgets that display
persistent countdown timers for active shifts and pass slips. Both auto-dismiss when
user completes the action. FCM handler triggers shift countdown on start_15 messages.
navigate_to field in data payload enables flexible routing to any screen.
Edge function: Updated process_scheduled_notifications to handle all 9 types with
appropriate titles, bodies, and routing. Includes pass_slip_id in idempotency tracking.
Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>