3b818dcd97
The /monitor WS proxy cancelled its sibling task on disconnect but then
`except Exception` failed to swallow the resulting CancelledError (a
BaseException), so stopping the stream raised "Exception in ASGI
application". It also only awaited the pending task, leaving the done
task's WebSocketDisconnect unretrieved ("Task exception was never
retrieved"). Await all tasks and catch (CancelledError, Exception).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>