[PULP-1749] Add migrate endpoint for push repositories

[gerrod3]

Summary

• Add a migrate action on push repositories that dispatches a task to convert ContainerPushRepository into ContainerRepository
• Support optional copy_versions to preserve full repository version history (defaults to copying only the latest version)
• Reassociate distributions, return the created repository in the task result, and add functional test coverage

Test plan

• Run pytest pulp_container/tests/functional/api/test_migrate_push_repository.py
• Verify POST /pulp/api/v3/repositories/container/container-push/{pk}/migrate/ returns 202 and completes successfully
• Confirm migrated repository appears under container repositories with preserved content and distribution link
• Test copy_versions: true when multiple repository versions exist

Made with Cursor

[mdellweg]

Do you plan to add a management command to migrate all remaining repositories?

Do you think we need to keep the old href's around as an alias? (Or by returning a clever redirect?)

[gerrod3]

Do you plan to add a management command to migrate all remaining repositories?

Yeah. I think I'll do it in a separate PR once I get this right.

Do you think we need to keep the old href's around as an alias? (Or by returning a clever redirect?)

No, this is one downside of the migration is that it's a completely new object, old hrefs won't work. I think it won't be a big deal since these repos are auto-created on push and auto-deleted when the distro is removed, so I don't expect many users are keeping track of these hrefs. Adding a compatibility layer is a lot of effort so my plan is to make the docs explicit on how the migration works so users understand what is happening.