repro websocket bug (#658)

There is a bug in the keepalive mechanism of the websocket library >
15.0 where a socket closure isn't propagated to recv(), which stays
blocked for ever. Fix by timing out during receive and reconnecting.

<img width="1012" height="218" alt="Screenshot 2026-04-08 at 16 42 22"
src="https://github.com/user-attachments/assets/fa7f9b48-c975-47de-8cd4-7addae8afc1b"
/>