feat:多跳（B->D->C->A）功能

cmd/internal/peer/kcp_client.go

@@ -32,8 +32,13 @@ func DialKCP(serverAddr, peerID string, opts ...Option) (*KCPClient, error) {
 		options.logger = latencylog.NoopLogger{}
 	}
 
+	dialAddr := serverAddr
+	if options.kcpDialAddress != "" {
+		dialAddr = options.kcpDialAddress
+	}
+
 	session, err := transport.DialKCPSession(
-		serverAddr,
+		dialAddr,
 		options.bindIP,
 		options.bindDevice,
 		options.kcpPacketDebugLogger,