docs(01-foundation): create phase plan

.planning/ROADMAP.md

@@ -29,7 +29,10 @@ Decimal phases appear between their surrounding integers in numeric order.
   3. All UI strings are loaded from ARB localization files — no hardcoded German text in Dart code
   4. The Drift database opens on first launch with schemaVersion 1 and the migration workflow is established (drift_dev make-migrations runs without errors)
   5. riverpod_lint is active and flags ref.watch usage outside build() as an analysis error
-**Plans**: TBD
+**Plans**: 2 plans
+Plans:
+- [ ] 01-01-PLAN.md — Scaffold Flutter project and build core infrastructure (database, providers, theme, localization)
+- [ ] 01-02-PLAN.md — Navigation shell, placeholder screens, Settings, and full app wiring
 
 ### Phase 2: Rooms and Tasks
 **Goal**: Users can create and manage rooms and tasks, mark tasks done, and trust the app to schedule the next occurrence automatically
@@ -77,7 +80,7 @@ Note: Phase 4 depends on Phase 2 (needs scheduling data) but can be developed in
 
 | Phase | Plans Complete | Status | Completed |
 |-------|----------------|--------|-----------|
-| 1. Foundation | 0/TBD | Not started | - |
+| 1. Foundation | 0/2 | Planning complete | - |
 | 2. Rooms and Tasks | 0/TBD | Not started | - |
 | 3. Daily Plan and Cleanliness | 0/TBD | Not started | - |
 | 4. Notifications | 0/TBD | Not started | - |