If I understand this correctly: The `active_repo_id` uses
`get_or_insert_with`, which makes it dependent on the `RepositoryAdded`
event sequence. To ensure correct initialization of the `active_repo_id`
on the remote side, the first local `RepositoryAdded` event must
synchronously send an `UpdateRepository` to `updates_tx`.

Closes #30694

Release Notes:

- Fixed incorrect default repository selection when using remote