Async equivalent of run_ws_stream.
Returns (async_message_iterator, async_control).
run_ws_stream_async(
dataplane_url: str,
api_key: Optional[str],
command: str,
*,
timeout: int = 60,
env: Optional[dict[str, str]] = None,
cwd: Optional[str] = None,
shell: str = '/bin/bash',
on_stdout: Optional[Callable[[str], Any]] = None,
on_stderr: Optional[Callable[[str], Any]] = None
) -> tuple[AsyncIterator[dict], _AsyncWSStreamControl]