Updated to Controllers/Document controllers

[OwainWilliams]

This pull request updates several controller endpoint summaries and descriptions to improve clarity and make them more specific to their actual functionality. The changes focus on making endpoint documentation more accurate and user-friendly, especially regarding document-related actions.

Improvements to endpoint documentation:

• Updated the summary and description for the UpdateDomainsController to clarify that it updates domains for a document, rather than the document itself.
• Updated the summary and description for the UpdateNotificationsController to specify that it updates notification subscriptions for a document and details which actions the current user is subscribed to.
• Updated the summary and description for the UpdatePublicAccessDocumentController to clarify that it updates public access protection and member protection settings for a document.
• Improved the description for the NotificationsController to accurately state that it gets notifications for a document, not notification settings.

General documentation cleanup:

• Removed redundant XML summary comments from the AllCultureController for consistency with other controllers.