As a user, I can copy content from one repository to another
The current repository modify endpoint calls the add_remove task which just adds or removes content to a repository. For users copying content between repos, this has been sufficient up until now as content is fully self contained. The problem though is with #7504 we are storing deprecated information per repository. So when content is copied over using the modify endpoint and add_remove task, that information is not being copied.
Add a copy endpoint similar to the one in pulp_rpm. This endpoint tasks a source repository version, a destination repository, and a set of content to be copied. It calls a new task (copy_content?) with these parameters and copies over the content plus any repository data (ie AnsibleCollectionDeprecated).