initial: Backend Auth Module + Design System + Complete Documentation

- Setup NestJS with TypeScript, ConfigModule, JWT authentication
- Implemented Auth Module with signup, login, logout endpoints
- Created DTOs with validation (SignupDto, LoginDto)
- JWT Strategy with Passport integration for token validation
- JwtAuthGuard for route protection with Bearer tokens
- CurrentUser decorator for dependency injection
- Supabase integration for user management and auth
- Complete API documentation (API.md) with all endpoints
- Design System for Web (Next.js + Tailwind) and Mobile (Flutter)
- Comprehensive project documentation and roadmap
- Environment configuration with Joi schema validation
- Ready for Tasks Module and RLS implementation

backend-api/.env.example

@@ -0,0 +1,29 @@
+# ======================================
+# SUPABASE CONFIGURATION
+# ======================================
+SUPABASE_URL=https://supabase.stackbackup.cloud
+SUPABASE_ANON_KEY=your_supabase_anon_key_here
+SUPABASE_SERVICE_KEY=your_supabase_service_key_here
+
+# ======================================
+# JWT CONFIGURATION
+# ======================================
+JWT_SECRET=your_jwt_secret_key_here_min_32_chars_long
+JWT_EXPIRATION=7d
+
+# ======================================
+# DATABASE CONFIGURATION
+# ======================================
+DATABASE_URL=postgresql://user:password@localhost:5432/taskmanager
+
+# ======================================
+# APP CONFIGURATION
+# ======================================
+NODE_ENV=development
+PORT=3000
+API_PREFIX=/api
+
+# ======================================
+# CORS CONFIGURATION
+# ======================================
+CORS_ORIGIN=http://localhost:3000,http://localhost:3001