Update: Based on further discoveries, the issue here seems thatcoderd web terminal sessions have gone defunct after the above error. As for what caused it? That's unknown at this time.

If I typecat /dev/zero in the web terminal, I observe 3 issues.

1. I see no output (Actually, this is normal forcat /dev/zero)
2. Opening a new web terminal simply freezes
3. Shortly thereafter, terminal session is closed via:WebSocket failed: socket errored
4. Web terminal to workspace seems permanently defunct, even after waiting a long time and ensuring processes inside the agent are terminated

This also has a pretty significant impact oncoderd CPU usage (#11039):

Refs#8556