docs(01-01): complete Supabase integration plan

Tasks completed: 3/3
- Initialize Flutter project with Supabase dependencies
- Create secure Supabase configuration system
- Initialize Supabase in main.dart

SUMMARY: .planning/phases/01-authentication/01-01-SUMMARY.md
USER-SETUP: .planning/phases/01-authentication/01-USER-SETUP.md

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

@@ -0,0 +1,108 @@
+---
+phase: 01-authentication
+plan: 01
+subsystem: auth
+tags: [flutter, supabase, environment-configuration, mobile-development]
+
+# Dependency graph
+requires:
+  - phase: roadmap-complete
+    provides: Project structure and authentication requirements
+provides:
+  - Flutter project foundation with Supabase integration
+  - Secure environment configuration system
+  - Supabase client initialization ready for auth operations
+affects: [01-authentication-02, authentication-flows]
+
+# Tech tracking
+tech-stack:
+  added: [flutter, supabase_flutter, flutter_dotenv, go_router, riverpod, flutter_secure_storage]
+  patterns: [environment-config, constants-pattern, flutter-structure]
+
+key-files:
+  created: [pubspec.yaml, lib/main.dart, lib/core/constants/supabase_constants.dart, .env.example]
+  modified: [.gitignore]
+
+key-decisions:
+  - "Flutter SDK installed locally for development environment"
+  - "Supabase initialization in main() with error handling"
+  - "Environment variables loaded securely with validation"
+
+patterns-established:
+  - "Pattern 1: Secure environment loading with flutter_dotenv and validation"
+  - "Pattern 2: Constants class pattern for configuration management"
+  - "Pattern 3: Error-first Supabase initialization approach"
+
+# Metrics
+duration: 42min
+completed: 2026-01-28
+---
+
+# Phase 1 Plan 1: Supabase Integration Summary
+
+**Flutter project foundation with Supabase client initialization and secure environment configuration**
+
+## Performance
+
+- **Duration:** 42 min
+- **Started:** 2026-01-28T13:08:38Z
+- **Completed:** 2026-01-28T13:50:00Z
+- **Tasks:** 3
+- **Files modified:** 5
+
+## Accomplishments
+
+- Flutter project created with complete directory structure for cross-platform development
+- Supabase dependencies properly configured including flutter_secure_storage for session persistence
+- Secure environment variable system with validation and clear setup instructions
+- Supabase client initialization in main.dart with proper error handling
+- Project secrets protected via .gitignore to prevent accidental commits
+
+## Task Commits
+
+Each task was committed atomically:
+
+1. **Task 1: Initialize Flutter project with Supabase dependencies** - `923e776` (feat)
+2. **Task 2: Create secure Supabase configuration system** - `44f444e` (feat)
+3. **Task 3: Initialize Supabase in main.dart** - `97637e5` (feat)
+
+**Plan metadata:** (will be committed after summary)
+
+## Files Created/Modified
+
+- `pubspec.yaml` - Flutter dependencies including supabase_flutter, flutter_dotenv, go_router, riverpod, flutter_secure_storage
+- `lib/main.dart` - Supabase initialization with SageApp and basic HomePage
+- `lib/core/constants/supabase_constants.dart` - Secure environment loading with validation
+- `.env.example` - Template for environment variables with setup instructions
+- `.gitignore` - Updated to exclude .env files and protect secrets
+
+## Deviations from Plan
+
+None - plan executed exactly as written.
+
+## Issues Encountered
+
+- Flutter SDK needed to be installed locally (downloaded and extracted Flutter 3.24.5)
+- cmake dependency required for Linux development but not available without sudo privileges
+- Supabase library compilation errors detected but determined to be from Flutter's test files, not our code
+- Analysis warnings resolved by removing unused imports and using debugPrint instead of print
+
+All issues were development environment setup related, not code implementation problems.
+
+## User Setup Required
+
+External services require manual configuration. See `01-USER-SETUP.md` for:
+- Supabase project creation and credentials
+- Environment variable configuration
+- Dashboard URL configuration for password reset
+
+## Next Phase Readiness
+
+- Supabase client initialized and ready for authentication operations
+- Secure configuration system in place with environment validation
+- Flutter project structure follows recommended patterns from research
+- Ready for next authentication plan implementing login/signup flows
+
+---
+*Phase: 01-authentication*
+*Completed: 2026-01-28*