remote: Fix incorrect default repository selection when using remote

[amtoaer]

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 (let's git together)

[cole-miller]

Thanks! I think this solution makes sense--what do you think about sending that initial UpdateRepository message whenever a new repo is inserted locally, regardless of whether it's the first? That seems a little cleaner and has the benefit that the downstream side's repository list will populate more promptly (even if it doesn't get the actual git statuses, etc. until later).

[cole-miller]

Thanks!

[esthertrapadoux]

Yeaaahhhh!!! Congrats @amtoaer !!