Improve message queue

[labrocadabro]

Placeholder, these issues should be fleshed out and created separately.

Issues:

• No error handling
• Queue is extremely rudimentary, doesn't even handled reconnection, only has 1 worker
• There's probably a better way to handle the publishing than just launching a new thread
• The web app will just send the URL(s) to the queue and report a success, the actual processing hasn't happened yet and there's no feedback to the user