// A minimal Proxy trait subset for the muxer. More methods
// (process_event, status, etc.) can be added as the async backend
// surfaces them.
use ;
/// A backend connected to a (local_port, peer_port) pair on the
/// muxer. Implementations:
/// tsi_stream::TsiStreamProxy — bridges to host TCP
/// echo (test only) — sends back what was received
/// Pack (local_port, peer_port) into a u64 key for the proxy map.