Server behaviour upon players joining/leaving is not open for extension

[asieradzk]

 private void Transport_OnRemoteConnectionState(RemoteConnectionStateArgs args)
        {
            //Sanity check to make sure transports are following proper types/ranges.
            int id = args.ConnectionId;
            int maxIdValue = short.MaxValue;
            if (id < 0 || id > maxIdValue)
            {
                Kick(args.ConnectionId, KickReason.UnexpectedProblem, LoggingType.Error, $"The transport you are using supplied an invalid connection Id of {id}. Connection Id values must range between 0 and {maxIdValue}. The client has been disconnected.");
                return;
            }
            //Valid Id.
            else
            {
                //If started then add to authenticated clients.
                if (args.ConnectionState == RemoteConnectionState.Started)
                {
                    NetworkManager.Log($"Remote connection started for Id {id}.");
                    NetworkConnection conn = new NetworkConnection(NetworkManager, id, args.TransportIndex, true);
                    Clients.Add(args.ConnectionId, conn);
                    OnRemoteConnectionState?.Invoke(conn, args);
                    //Connection is no longer valid. This can occur if the user changes the state using the OnRemoteConnectionState event.
                    if (!conn.IsValid)
                        return;
                    /* If there is an authenticator
                     * and the transport is not a local transport. */
                    Authenticator auth = GetAuthenticator();
                    if (auth != null && !NetworkManager.TransportManager.IsLocalTransport(id))
                        auth.OnRemoteConnection(conn);
                    else
                        ClientAuthenticated(conn);
                }
                //If stopping.
                else if (args.ConnectionState == RemoteConnectionState.Stopped)
                {
                    /* If client's connection is found then clean
                     * them up from server. */
                    if (Clients.TryGetValueIL2CPP(id, out NetworkConnection conn))
                    {
                        conn.SetDisconnecting(true);
                        OnRemoteConnectionState?.Invoke(conn, args);
                        Clients.Remove(id);
                        Objects.ClientDisconnected(conn);
                        BroadcastClientConnectionChange(false, conn);
                        //Return predictedObjectIds.
                        Queue<int> pqId = conn.PredictedObjectIds;
                        while (pqId.Count > 0)
                            Objects.CacheObjectId(pqId.Dequeue());

                        conn.Dispose();
                        NetworkManager.Log($"Remote connection stopped for Id {id}.");
                    }
                }
            }
        }
        ```
        


This method here as far as I know is the only logic getting executed on ServerManager when player join/leave. If I want to execute some arbitrary code using ConnId and conn as arguments I will not be able to do it without significantly editing the ServerManager.cs which is not ideal since things will likely break on update.

I see two ways to fix this:
1. Fire an event when this method is called (im going to do this now). This is great but doesnt leave much wiggle room for modifying joining flow (what if I want conn to jump some extra hoops?)
2. Have to separate virtual methods for OnPlayerJoined, OnPlayerLeft or ifits such a big deal make Transport_OnRemoteConnectionState a single virtual method.

[asieradzk]

Nevermind I see I can make this work with OnRemoteConnectionState

Lets roll with that instead and make encapsulating class