Refactor queue system into modular structure

- Created new queue module with separate components:
  - models.py: QueueItem and QueueMetrics data classes
  - persistence.py: Queue state persistence
  - monitoring.py: Health monitoring and metrics
  - cleanup.py: Cleanup operations
  - manager.py: Main queue management
  - __init__.py: Package exports

- Updated imports in video_archiver.py and processor.py
- Removed old enhanced_queue.py
- Updated README with new queue system details

This refactoring improves code organization and maintainability
through better separation of concerns while maintaining all
existing functionality.

videoarchiver/processor.py

@@ -11,7 +11,7 @@ from typing import Dict, Any, Optional, Tuple, Set
 import traceback
 from datetime import datetime
 
-from videoarchiver.enhanced_queue import EnhancedVideoQueueManager
+from videoarchiver.queue import EnhancedVideoQueueManager  # Updated import
 from videoarchiver.utils.exceptions import (
     ProcessingError,
     ConfigurationError,