NanoMQ: QUIC Dialer Close Type Confusion

NanoMQ MQTT Broker (NanoMQ) is an all-around Edge Messaging Platform. Prior to 0.24.14, aio->prov_data is stored as nni_quic_conn* during dialing, but read as ex_quic_conn* during dialer close. This type confusion causes invalid object interpretation and leads to close-path hang/crash behavior. This vulnerability is fixed in 0.24.14.