- Create apps/api/src/broker/reminderScheduler.ts:
- runReminderCheck(now): queries isShared=true + allDay=false events
with dtstartUtc in [now+14min, now+16min] via calendarEvents→calendars→
pushSubscriptions cross-join (2 innerJoins; fans out to all subscribers)
- In-memory sentReminders Set keyed uid:minuteBucket prevents double-fire
at window boundary (D-06, T-05-18)
- Per-event and per-subscription try/catch for error isolation (T-05-19)
- Null title fallback (event.title ?? uid) — handles rows before Plan 05-07
- Empty shared-calendar set produces zero sends and no crash (D-16)
- startReminderScheduler(): node-cron 1-min schedule wrapping runReminderCheck
- Wire startReminderScheduler() into index.ts isMainModule() guard after
startOutboxWorker() and VAPID setVapidDetails (NOTIF-01)
- Tests: 3/3 GREEN (all-day excluded, non-shared excluded, dedup)