* Add CreateCollectionCommand and associated interface with validation logic
* Implement CreateCollectionCommand to handle collection creation with organization checks and access permissions.
* Introduce ICreateCollectionCommand interface for defining the collection creation contract.
* Add unit tests for CreateCollectionCommand to validate various scenarios including permission checks and error handling.
* Add UpdateCollectionCommand and associated interface with validation logic
* Implement UpdateCollectionCommand to handle collection updates with organization checks and access permissions.
* Introduce IUpdateCollectionCommand interface for defining the collection update contract.
* Add unit tests for UpdateCollectionCommand to validate various scenarios including permission checks and error handling.
* Add scoped services for collection commands
* Register ICreateCollectionCommand and IUpdateCollectionCommand in the service collection for handling collection creation and updates.
* Refactor CollectionsController to use command interfaces for collection creation and updates
* Updated CollectionsController to utilize ICreateCollectionCommand and IUpdateCollectionCommand for handling collection creation and updates, replacing calls to ICollectionService.
* Adjusted related unit tests to verify the new command implementations.
* Refactor ICollectionService and CollectionService to remove SaveAsync method
* Removed the SaveAsync method from ICollectionService and its implementation in CollectionService.
* Updated related tests in CollectionServiceTests to reflect the removal of SaveAsync, ensuring existing functionality remains intact.
* Remove unused organization repository dependency from CollectionServiceTests
