fix: run disconnect callback before internal disconnect logic (#1221) (#1467)

* fix: run disconnect callback before internal disconnect logic

* fix: standards.py

Co-authored-by: Luke Stampfli <43687322+LukeStampfli@users.noreply.github.com>

Author: andrews-unity

com.unity.netcode.gameobjects/Runtime/Core/NetworkManager.cs

@@ -345,8 +345,6 @@ public IReadOnlyList<ulong> ConnectedClientsIds
         /// </summary>
         public event Action<ulong> OnClientDisconnectCallback = null;
 
-        internal void InvokeOnClientDisconnectCallback(ulong clientId) => OnClientDisconnectCallback?.Invoke(clientId);
-
         /// <summary>
         /// The callback to invoke once the server is ready
         /// </summary>
@@ -1310,6 +1308,8 @@ private void HandleRawTransportPoll(NetworkEvent networkEvent, ulong clientId, A
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
                     s_TransportDisconnect.Begin();
 #endif
+                    OnClientDisconnectCallback?.Invoke(clientId);
+
                     clientId = TransportIdToClientId(clientId);
 
                     m_TransportIdToClientIdMap.Remove(transportId);
@@ -1328,9 +1328,6 @@ private void HandleRawTransportPoll(NetworkEvent networkEvent, ulong clientId, A
                     {
                         Shutdown();
                     }
-
-                    OnClientDisconnectCallback?.Invoke(clientId);
-
 #if DEVELOPMENT_BUILD || UNITY_EDITOR
                     s_TransportDisconnect.End();
 #endif