Add background task updates to user

[CollinHeist]

Similar to #354 , and maybe is superseded by it, but the status of functions executing in BackgroundTasks should be visible to the user.

I think the two options for implementation are essentially polling vs. interrupts, e.g.:

• Add a scheduled API call to query for new messages - maybe /api/messages or something
• Open a WebSocket on all pages that is interrupted by new messages

Here is an interesting about when to use either.

---

I'm not sold on either, but maybe the WebSocket approach would be better?

[CollinHeist]

I had a lot of issues with the WebSocket not triggering properly on all browsers, so I went with a polled endpoint instead