Add backend for version naming

[artonge]

TODO

• Create oc_files_versions table with id, file_id?, version_id, name, and author for future.
• Plug into DAV plugin
• Check current ajax routes
• Expose endpoint to name a version
• Expose endpoint to create a new version from the current version
• Expose endpoint to delete a version
• Checkout S3 and group folders implementation as Carl raise some concerns
• Remove experimental flag on UI

Follow up

• Use COPY instead of MOVE when restoring version, so that it stays in the history (if not already the case)
• Disable cleanup of named version in files_versions/lib/Storage.php

Need #35080