Function get_or_init_channel_mux 

pub fn get_or_init_channel_mux() -> Arc<ChannelMux>

Available on crate feature deploy and (crate features docker_runtime or ecs_runtime) only.

Get or initialize the global ChannelMux for this process.

The first call creates the TcpListener and spawns the accept loop. Subsequent calls return the same Arc<ChannelMux>.