Dotnet version upgrade

Room/Messages/ChatMessage.cs

@@ -2,6 +2,7 @@
 
 public class ChatMessage
 {
+    public Guid Id { get; set; } = Guid.NewGuid();
     public string Sender { get; set; }
     public string Message { get; set; }
     

Room/Messages/EndMessage.cs

@@ -1,13 +1,13 @@
-namespace MauMau_Server.Room.Messages;
+using MauMau_Server.Websockets;
+
+namespace MauMau_Server.Room.Messages;
 
 public class EndMessage
 {
-    public Guid WinnerId { get; set; }
-    public string WinnerName { get; set; }
+    public ConnectionInstance Winner { get; set; }
     
-    public EndMessage(Guid winnerId, string winnerName)
+    public EndMessage(ConnectionInstance winner)
     {
-        WinnerId = winnerId;
-        WinnerName = winnerName;
+        Winner = winner;
     }
 }

Room/Room.cs

@@ -3,7 +3,6 @@ using System.Text.Json;
 using System.Text.RegularExpressions;
 using MauMau_Server.Room.Messages;
 using MauMau_Server.Websockets;
-using Microsoft.AspNet.SignalR.Messaging;
 
 namespace MauMau_Server.Room;
 
@@ -11,7 +10,7 @@ public class Room
 {
     private readonly IRoomManager _roomManager;
     private readonly string _roomId;
-    public readonly List<ConnectionInstance> Connections = new();
+    public readonly List<ConnectionInstance> Connections = [];
     public ConnectionInstance? Host;
     public RoomType RoomType;
 

Room/RoomMessage.cs

@@ -1,4 +1,4 @@
-using Newtonsoft.Json;
+using System.Text.Json;
 
 namespace MauMau_Server.Room;
 
@@ -10,7 +10,7 @@ public class RoomMessage<T>
     public RoomMessage(string type, T data)
     {
         Type = type;
-        Data = JsonConvert.SerializeObject(data);
+        Data = JsonSerializer.Serialize(data);
     }
     
     public RoomMessage()