fix(mqtt): avoid driver deadlock when re-subscribing many filters#18
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On (re)connect the shared-connection driver re-subscribed every mqtt-in filter inline with `client.subscribe().await`. Each call only enqueues a request into a bounded channel (capacity 10) that is drained solely by the driver's own `poller.poll()`. Awaiting the subscribes inline meant the driver was not polling, so once the queue filled the next subscribe blocked forever, deadlocking the whole connection: no further subscribes completed and no publishes were sent. A flow with more than ~10 mqtt-in nodes on one shared broker therefore went completely silent on connect. Move the re-subscribe + birth publish into a detached task so the event loop keeps polling and the request queue drains.
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On (re)connect the shared-connection driver re-subscribed every mqtt-in filter inline with
client.subscribe().await. Each call only enqueues a request into a bounded channel (capacity 10) that is drained solely by the driver's ownpoller.poll(). Awaiting the subscribes inline meant the driver was not polling, so once the queue filled the next subscribe blocked forever, deadlocking the whole connection: no further subscribes completed and no publishes were sent.A flow with more than ~10 mqtt-in nodes on one shared broker therefore went completely silent on connect. Move the re-subscribe + birth publish into a detached task so the event loop keeps polling and the request queue drains.