### CHANGES
- Add early return if registry is nil to prevent panics.
- Introduce early return for non-chat tool operations.
- Update error message to use original input on HTML readability failure.
- Enhance error wrapping for playlist video fetching.
- Modify temp patterns folder name with timestamp for uniqueness.
- Improve error handling for patterns directory access.
### CHANGES
* Extract chat processing logic into separate function
* Create modular command handlers for setup, configuration, listing, management, and extensions
* Improve patterns loader with migration support and better error handling
* Simplify main CLI logic by delegating to specialized handlers
* Enhance code organization and maintainability
* Add tool processing for YouTube and web scraping functionality