lark_oapi parks Client.start() in run_until_complete(_select()) and runs
the receive loop as a bare create_task whose exception nobody retrieves.
With Hermes disabling the SDK's reconnect ladder, a mid-life receive-loop
death leaves a deaf-but-ESTABLISHED socket: start() never returns, the
supervisor's executor future never completes, and gateway_state.json keeps
reporting connected (#113662).
Wrap Client._receive_message_loop in the existing isolation installer so
its exit stops the worker loop; start() then raises, the future completes,
and _supervise_websocket_thread rebuilds the link with its capped backoff.
Deliberate disconnects stay unaffected: they nil _ws_client first and the
supervisor exits without restarting.
Fixes#113662
5743dbb703