No strong indicator when waiting for files from host

[iamnbutler]

From discord:

I don't know if y'all have experienced this but if you are a collaborator and the host has a slow connection, you can join a project and have nearly nothing in the project browser.

My hypothesis is that this happens when you hit downloading node_modules, so it can look like nothing is loading for ~10-20 seconds. Then suddenly all the files pop in to the project browser.

We probably need some sort of state to tell the collaborator they are still streaming the files from the host.

This feels extra bad, because if the host is in a file you don't have yet and try to follow them you just get a blank pane, and if you try to cmd+p to a file you know exists it will just not show up.