- Add async_download() and async_rescan() methods for non-blocking operations
- Implement ProgressInfo dataclass for structured progress reporting
- Add OperationResult dataclass for operation outcomes
- Introduce OperationStatus enum for state tracking
- Add cancellation support with cancel_operation() method
- Implement comprehensive error handling with callbacks
- Add progress_callback and error_callback support in constructor
- Create 22 comprehensive unit tests for all functionality
- Update infrastructure.md with core logic documentation
- Remove completed task from instructions.md
This enhancement enables web integration with real-time progress updates,
graceful cancellation, and better error handling for long-running operations.
