fix: 解决json无法正常解析的问题

cmd/client/main.go

@@ -57,13 +57,12 @@ func main() {
 
 func ReadBroadCastLoop(ctx context.Context, c *websocket.Conn) {
 	for {
-		// var msg protocol.BroadcastMessage
-		var msg []byte
+		var msg protocol.BroadcastMessage
 		if err := wsjson.Read(ctx, c, &msg); err != nil {
-			log.Println("read broadcast error:", err)
+			log.Println("Read broadcast error:", err)
 			return
 		}
 
-		log.Println("Received broadcast message:", string(msg))
+		log.Printf("Received broadcast message: [%s] %s", msg.Topic, msg.Payload)
 	}
 }