[ISSUE #4025]Introduce ChannelId type alias for improved clarity in channel struct (#4026)

Author: mxsm

rocketmq-remoting/src/net/channel.rs

@@ -35,12 +35,14 @@ use crate::base::response_future::ResponseFuture;
 use crate::connection::Connection;
 use crate::protocol::remoting_command::RemotingCommand;
 
+pub type ChannelId = CheetahString;
+
 #[derive(Clone)]
 pub struct Channel {
     inner: WeakArcMut<ChannelInner>,
     local_address: SocketAddr,
     remote_address: SocketAddr,
-    channel_id: CheetahString,
+    channel_id: ChannelId,
 }
 
 impl Channel {