Improve external services admin experience

Created by: eseliger

I've been trying to look into some issues and the pages were way too stale, also we had lots of information already fetched even that we didn't surface in the UI. This PR mainly does 2 things:

• It adds much more context to the list page, so it's easy to see at a glance: What is working, what is not working, are we syncing?
• It adds syncer information to the external service info page, so that admins can quickly see is the error always happening, what is the error message (I don't think we surfaced that in the UI before at all?) and give them the ability to trigger another lazy sync, so that network blips can be investigated more easily.

I hope this helps a bit with admin experience and debugging.

Test plan

Tested the flows manually pretty thoroughly.