- Add comprehensive user schemas with email validation
- Implement enhanced todo schemas with priority levels, tags, due dates, and subtasks
- Add support for recurring todos with pattern validation
- Include sharing schemas for collaborative features
- Add proper validation rules and field constraints
- Create response schemas for API pagination and collections
- Include authentication and API response schemas
- Add comprehensive documentation strings for all schema classes
- Add User model with email-based authentication
- Add Tag model with many-to-many relationship to todos
- Add TodoTag junction table for todo-tag relationships
- Enhance Todo model with priority levels (low, medium, high)
- Add due_date field with datetime support
- Add recurrence_pattern field for recurring todos
- Add parent-child relationship for subtasks support
- Create comprehensive alembic migration for all changes
- Add proper indexes for performance optimization
- Use Text type for todo descriptions
- Implement proper SQLAlchemy relationships and foreign keys
- Create FastAPI application with CORS support
- Add SQLAlchemy models for Todo with timestamps
- Set up SQLite database with proper configuration
- Create CRUD operations for todo management
- Add REST API endpoints for all todo operations
- Configure Alembic for database migrations
- Add Pydantic schemas for request/response validation
- Include health check and root info endpoints
- Set up proper project structure following best practices
- Add comprehensive README with usage instructions
