docs(phase-2): complete context and implementation planning

- Documented comprehensive plan for Phase 2: Rooms and Tasks
- Includes feature scope, requirements, implementation decisions, UI/UX specifics, and scheduling logic
- Updated schema: added Room and Task tables with CRUD and recurrence support
- Added implementation details for room/task templates, cleanliness indicators, and overdue task handling
- Generated Drift schemas for database versioning (v1 → v2) with test coverage

pubspec.yaml

@@ -22,7 +22,7 @@ dependencies:
   flutter_reorderable_grid_view: ^5.6.0
   flutter_local_notifications: ^21.0.0
   timezone: ^0.11.0
-  flutter_timezone: ^1.0.8
+  flutter_timezone: ^5.0.2
 
 dev_dependencies:
   flutter_test: