完成离线消息发送和上线获取离线消息

Hotfix/Chat/Handler/C2Chat_GetOfflineMessageRequestHandler.cs

@@ -0,0 +1,24 @@
+using Fantasy;
+using Fantasy.Async;
+using Fantasy.Network.Interface;
+
+namespace NB.Chat;
+
+public class
+    C2Chat_GetOfflineMessageRequestHandler : RouteRPC<ChatUnit, C2Chat_GetOfflineMessageRequest,
+    Caht2C_GetOfflineMessageResponse>
+{
+    protected override async FTask Run(ChatUnit entity, C2Chat_GetOfflineMessageRequest request,
+        Caht2C_GetOfflineMessageResponse response,
+        Action reply)
+    {
+        var chatUnitManage = entity.Scene.GetComponent<ChatUnitManageComponent>();
+        if (chatUnitManage.NotSendMessage.TryGetValue(entity.Id, out var list))
+        {
+            response.Message.AddRange(list);
+            chatUnitManage.NotSendMessage.RemoveByKey(entity.Id);
+        }
+
+        await FTask.CompletedTask;
+    }
+}