docs(01-04): complete auth repository and state management plan

Tasks completed: 2/2
- AuthRepositoryImpl with Supabase integration
- AuthProvider with Riverpod state management

SUMMARY: .planning/phases/01-authentication/01-04-SUMMARY.md

.planning/phases/01-authentication/01-04-SUMMARY.md

@@ -0,0 +1,109 @@
+---
+phase: 01-authentication
+plan: 04
+subsystem: auth
+tags: [supabase, flutter, riverpod, authentication, state-management]
+
+# Dependency graph
+requires:
+  - phase: 01-authentication
+    provides: AuthRepository interface, AuthUser model, custom exception hierarchy
+provides:
+  - Supabase authentication repository implementation
+  - Global authentication state management with Riverpod
+  - Auth state persistence across app restarts
+  - Automatic UI updates on auth state changes
+affects: [01-05-router-integration, 02-household-creation]
+
+# Tech tracking
+tech-stack:
+  added: []
+  patterns: [repository-pattern, state-management, clean-architecture, dependency-injection]
+
+key-files:
+  created: 
+    - lib/features/authentication/data/repositories/auth_repository_impl.dart
+    - lib/providers/auth_provider.dart
+  modified: []
+
+key-decisions:
+  - "Used Riverpod for state management (flutter_riverpod package already in dependencies)"
+  - "Implemented complete AuthRepository interface with all required methods"
+  - "Created AuthState class with loading, error, and user management"
+  - "Added convenience providers for common auth state access patterns"
+
+patterns-established:
+  - "Pattern 1: Repository implementation with comprehensive error mapping"
+  - "Pattern 2: StateNotifier pattern for global state management"
+  - "Pattern 3: Provider composition for granular state access"
+
+# Metrics
+duration: 8 min
+completed: 2026-01-28
+---
+
+# Phase 1 Plan 04: Auth Repository and State Management Summary
+
+**Supabase authentication repository with Riverpod global state management, implementing complete auth interface with automatic UI updates**
+
+## Performance
+
+- **Duration:** 8 min
+- **Started:** 2026-01-28T15:33:07Z
+- **Completed:** 2026-01-28T15:40:45Z
+- **Tasks:** 2
+- **Files modified:** 2
+
+## Accomplishments
+- Complete AuthRepository implementation using Supabase authentication methods
+- Global authentication state management with Riverpod StateNotifier
+- Automatic UI updates through auth state change streams
+- Comprehensive error handling with custom exception mapping
+- Loading state management for all authentication operations
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Implement AuthRepository with Supabase** - `294d537` (feat)
+2. **Task 2: Create AuthProvider for state management** - `f3397a9` (feat)
+
+**Plan metadata:** (will be committed with summary)
+
+## Files Created/Modified
+
+- `lib/features/authentication/data/repositories/auth_repository_impl.dart` - Complete Supabase auth implementation with all interface methods
+- `lib/providers/auth_provider.dart` - Riverpod state management with AuthState class and convenience providers
+
+## Decisions Made
+
+- Used Riverpod StateNotifier for authentication state management (consistent with project dependencies)
+- Implemented comprehensive AuthRepository interface covering all authentication use cases
+- Created AuthState class to encapsulate user, loading, and error states
+- Added convenience providers for common UI state access patterns (currentUser, isAuthenticated, isLoading, error)
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+
+None - implementation proceeded smoothly without issues.
+
+## User Setup Required
+
+None - no external service configuration required for this plan.
+
+## Next Phase Readiness
+
+Authentication foundation is now complete with:
+- AuthRepository implementation ready for Supabase integration
+- Global state management that automatically responds to auth changes
+- Error handling and loading states properly implemented
+- Session persistence will be handled by Supabase automatically
+
+Ready for next phase: 01-05-router-integration (navigation and auth guards).
+
+---
+*Phase: 01-authentication*
+*Completed: 2026-01-28*