docs(04): create phase plan

.planning/ROADMAP.md

@@ -79,7 +79,11 @@ Plans:
   2. User can enable or disable notifications from the Settings tab, and the change takes effect immediately
   3. Notifications are correctly rescheduled after device reboot (RECEIVE_BOOT_COMPLETED receiver active)
   4. On Android API 33+, the app requests POST_NOTIFICATIONS permission at the appropriate moment and degrades gracefully if denied
-**Plans**: TBD
+**Plans**: 3 plans
+Plans:
+- [ ] 04-01-PLAN.md — Infrastructure: packages, Android config, NotificationService, NotificationSettingsNotifier, DAO queries, timezone init, tests
+- [ ] 04-02-PLAN.md — Settings UI: Benachrichtigungen section with toggle, time picker, permission flow, scheduling wiring, tests
+- [ ] 04-03-PLAN.md — Verification gate: dart analyze + full test suite + requirement confirmation
 
 ## Progress
 
@@ -93,4 +97,4 @@ Note: Phase 4 depends on Phase 2 (needs scheduling data) but can be developed in
 | 1. Foundation | 2/2 | Complete    | 2026-03-15 |
 | 2. Rooms and Tasks | 5/5 | Complete    | 2026-03-15 |
 | 3. Daily Plan and Cleanliness | 3/3 | Complete   | 2026-03-16 |
-| 4. Notifications | 0/TBD | Not started | - |
+| 4. Notifications | 0/3 | In progress | - |