[temp fix] Always delete client YDoc on disconnect

[dlqqq]

Description

• Fixes Repeated handshakes on outdated clients #39

yprovider.ts deletes the client YDoc & stops retrying the connection only when the WS close code is 1006. This indicates an unexpected closure (e.g. via kill -9 <PID>). However, our backend should close each WebSocket gracefully before exiting; this sends close code 1000, which gets ignored by yprovider.ts. This causes re-connect attempts to fire constantly from outdated clients after the server is restarted.

This PR simply removes the if (event.code === 1006) condition and always deletes the client YDoc & stops retrying the connection on disconnect. This fixes #39 and prevents content duplication when an outdated client connects to a new server session.

While this PR does fix the edge cases, it also worsens the experience for users with a flaky internet connection, who now have to refresh the page manually every time they are disconnected. We can improve this in future PRs; I've identified ways to handle client disconnects more gracefully in a new issue: #45.

[3coins]

This is still happening for me, after any refresh (even without restarting the server).

Screen.Recording.2025-05-14.at.3.00.23.PM.mov

[dlqqq]

@3coins This might be because you need to rebuild the frontend before trying to reproduce the original bug. The sequencing is a bit tricky. Can you try these steps below?

1. Checkout & pull this branch
2. Run jlpm && jlpm build
3. Run jupyter lab to open a new window
4. Kill jupyter lab and restart it
5. The original (first) window should no longer constantly re-connect

[3coins]

Looks good!
Was able to verify that during server disconnects, clients don't try to re-connect, but show a dialog to refresh page. The browser refresh issue mentioned in one of my comments is being tracked in #51 and is a different problem.