chore: complete v1.0 MVP milestone

Archive roadmap and requirements to milestones/, evolve PROJECT.md
with validated requirements and decision outcomes, reorganize
ROADMAP.md with milestone grouping, create retrospective.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.planning/RETROSPECTIVE.md

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+# Project Retrospective
+
+*A living document updated after each milestone. Lessons feed forward into future planning.*
+
+## Milestone: v1.0 — MVP
+
+**Shipped:** 2026-03-16
+**Phases:** 4 | **Plans:** 13
+
+### What Was Built
+- Complete room-based household chore app with auto-scheduling task management
+- Daily plan home screen with overdue/today/tomorrow sections and progress tracking
+- Bundled German task templates for 14 room types
+- Daily summary notifications with configurable time and Android permission handling
+- 89 tests covering DAOs, scheduling logic, providers, and widget behavior
+
+### What Worked
+- Bottom-up phase structure (foundation -> data -> UI -> polish) kept each phase clean with minimal rework
+- TDD approach for providers and services caught several issues early (async race conditions, API mismatches)
+- Verification gates at the end of Phase 2, 3, and 4 confirmed all requirements before moving on
+- Calendar-anchored scheduling with anchor memory was designed right the first time — no rework needed
+- ARB localization from Phase 1 meant adding German strings was frictionless throughout
+
+### What Was Inefficient
+- riverpod_generator InvalidTypeException with drift Task type required workaround (manual StreamProvider) in 3 separate plans — should have been caught in Phase 1 research
+- Some plan specifications referenced outdated API patterns (flutter_local_notifications positional parameters removed in v20+) — research needs to verify exact current API signatures
+- Phase 4 plan checkboxes in ROADMAP.md weren't updated to [x] by executor — minor bookkeeping gap
+
+### Patterns Established
+- `@Riverpod(keepAlive: true)` AsyncNotifier with SharedPreferences for persistent settings (ThemeNotifier, NotificationSettingsNotifier)
+- Manual StreamProvider.family/autoDispose for drift type compatibility
+- DailyPlanDao innerJoin pattern for cross-table queries
+- ConsumerStatefulWidget for screens with async callbacks requiring `mounted` guards
+- Provider override pattern in widget tests for database isolation
+
+### Key Lessons
+1. Research phase should verify exact current package API signatures — breaking changes between major versions cause plan deviations
+2. Drift + riverpod_generator type incompatibility is a known issue — plan for manual providers from the start when using drift
+3. Verification gates add minimal time (~2 min) but catch integration issues — keep them for all phases
+4. Progressive disclosure (AnimatedSize) is a clean pattern for conditional settings UI
+
+### Cost Observations
+- Model mix: orchestrator on opus, researchers/planners/executors/checkers on sonnet
+- Total execution: ~1.3 hours for 13 plans across 4 phases
+- Notable: Verification gates averaged 2 min — very efficient for the confidence they provide
+
+---
+
+## Cross-Milestone Trends
+
+### Process Evolution
+
+| Milestone | Phases | Plans | Key Change |
+|-----------|--------|-------|------------|
+| v1.0 | 4 | 13 | Initial project — established all patterns |
+
+### Cumulative Quality
+
+| Milestone | Tests | Key Metric |
+|-----------|-------|------------|
+| v1.0 | 89 | dart analyze clean, 0 issues |
+
+### Top Lessons (Verified Across Milestones)
+
+1. (Single milestone — lessons above will be cross-validated as more milestones ship)