[edit] Destroy stale collab sessions

[auniverseaway]

As an author, I would like my old collab sessions to expire after X min so that my background tabs are not wasting precious resources.

Criteria of acceptance

1. On window blur + 10 minutes of inactivity, the collab session is closed.
2. On window focus the collab session is restored.
3. Nice to have - I have historically opposed this, but it may be nice to have some indication of the collab session resuming. Ideally a simple icon so its language agnostic.

Additional context

It's common to switch between tabs while multi tasking... copy/pasting between docs, etc. so we do not want to destroy collab immediately. I think we start with a 10 minute threshold and see how things go.