Shuttle/uppy error handling

[jszobody]

I was able to get into a pretty broken state just now:

Trying to upload 4 files. 2 worked, 1 failed at 100%, 1 is just spinning in progress.

The main issue here though is that the page is now broken hard. I can't even retry the failed file:

We have to figure out some way to catch JS errors with the upload process, log them, display them, do whatever we need to do... but ensure the page isn't left completely broken.