Slowly loading cloud agents steal focus when loading after switching

[digitarald]

Cloud agents take a 5s+ seconds to load for me.

1. Click a cloud agent session
2. Click away to another agent in a list
3. 🐛 Once previous cloud agent teal the focus while the new agent I selected is still picked.

https://github.com/user-attachments/assets/5cb230d5-4762-43ec-a922-dcf33405caee

[joshspicer]

One obvious improvement here is that we should cancel loading when you swap to another chat session.

Even better is make loading of a cloud session super fast

[rebornix]

One obvious improvement here is that we should cancel loading when you swap to another chat session.

+1. this is the bug I ran into this morning when I was sharing my screen. opening a session should cancel all previous session opening in the sidebar.

[joshspicer]

I do not repro the cancellation errors. This will need more thought on how to better load resources remotely from github (as that is what takes the longest time here)