add: 基础的聊天对话框

Frontend/Models/ChatMessage.cs

@@ -0,0 +1,10 @@
+namespace Frontend.Models;
+
+public class ChatMessage
+{
+    public required string Sender { get; init; }
+        
+    public required string Text { get; init; }
+        
+    public required bool Left { get; init; }
+}