- Added category field to Todo model for organizing todos
- Added due_date field with timezone support for deadline tracking
- Enhanced CRUD operations with filtering by category, completion status, and overdue items
- Added new API endpoints for category-based and overdue todo retrieval
- Updated API documentation with new filtering query parameters
- Created database migration for new fields with proper indexing
- Updated README with comprehensive feature documentation
- Add SQLAlchemy models for Todo with timestamps
- Create Pydantic schemas for request/response validation
- Implement CRUD operations for Todo management
- Add REST API endpoints for todo operations (GET, POST, PUT, DELETE)
- Configure SQLite database with proper connection settings
- Set up Alembic migrations for database schema management
- Add comprehensive API documentation and health check endpoint
- Enable CORS for all origins
- Include proper error handling and HTTP status codes
- Update README with complete setup and usage instructions
