docs(11): create per-event-reminders phase plan (4 plans, 3 waves)

.planning/ROADMAP.md

@@ -212,7 +212,14 @@ Plans:
   - **uid:dtstartMs dedup** (Pitfall 4): change the scheduler dedup key from bare `uid` to compound `uid:dtstartMs` and widen the scan to a variable per-event window so long leads fire and rescheduled events re-fire; keep `eventFieldsSchema` and `outboxPayloadSchema` in sync (IN-03).
   - Hard constraints: `setInterval` only; scheduler reads `reminder_lead_minutes` from the DB (ground truth), not the outbox payload; drop the `isShared`-only reminder restriction (a user who set an alarm wants it regardless of calendar).
 
-**Plans**: TBD
+**Plans**: 4 plans (3 waves)
+
+Plans:
+- [ ] 11-01-PLAN.md — VALARM builders + classifier + extractor + computeAlertInstantUtc (vevent.ts, TDD)
+- [ ] 11-02-PLAN.md — Variable-lead scheduler: uid:dtstartMs dedup, drop isShared, all-day 9 AM, humanized body (TDD)
+- [ ] 11-03-PLAN.md — Backend plumbing: schema field, outbox preserve-on-edit, sync upsert, occurrence surfacing
+- [ ] 11-04-PLAN.md — EventForm reminder picker (allDay swap, edit pre-population) + client types + Playwright smoke
+
 **UI hint**: yes
 
 ### Phase 12: Initial Setup Wizard