- Updated the `GetCollection` method to first read from the database for existence and permissions, improving data integrity.
- Merged metadata from GraphRag into the result, ensuring backward compatibility and enhanced data representation.
- Refactored the `CollectionExists` method to check both the database and GraphRag for consistency, logging any mismatches for debugging purposes.
- Introduced new types and structures for search operations, including `SearchMode`, `Query`, and `SearchResult`, to support advanced search functionalities.
