Seal/abstract/virtual everything (#6739)

Content.Shared/GameTicking/SharedGameTicker.cs

@@ -17,17 +17,17 @@ namespace Content.Shared.GameTicking
     }
 
     [Serializable, NetSerializable]
-    public class TickerJoinLobbyEvent : EntityEventArgs
+    public sealed class TickerJoinLobbyEvent : EntityEventArgs
     {
     }
 
     [Serializable, NetSerializable]
-    public class TickerJoinGameEvent : EntityEventArgs
+    public sealed class TickerJoinGameEvent : EntityEventArgs
     {
     }
 
     [Serializable, NetSerializable]
-    public class TickerLateJoinStatusEvent : EntityEventArgs
+    public sealed class TickerLateJoinStatusEvent : EntityEventArgs
     {
         // TODO: Make this a replicated CVar, honestly.
         public bool Disallowed { get; }
@@ -40,7 +40,7 @@ namespace Content.Shared.GameTicking
 
 
     [Serializable, NetSerializable]
-    public class TickerLobbyStatusEvent : EntityEventArgs
+    public sealed class TickerLobbyStatusEvent : EntityEventArgs
     {
         public bool IsRoundStarted { get; }
         public string? LobbySong { get; }
@@ -60,7 +60,7 @@ namespace Content.Shared.GameTicking
     }
 
     [Serializable, NetSerializable]
-    public class TickerLobbyInfoEvent : EntityEventArgs
+    public sealed class TickerLobbyInfoEvent : EntityEventArgs
     {
         public string TextBlob { get; }
 
@@ -71,7 +71,7 @@ namespace Content.Shared.GameTicking
     }
 
     [Serializable, NetSerializable]
-    public class TickerLobbyCountdownEvent : EntityEventArgs
+    public sealed class TickerLobbyCountdownEvent : EntityEventArgs
     {
         /// <summary>
         /// The game time that the game will start at.
@@ -91,7 +91,7 @@ namespace Content.Shared.GameTicking
     }
 
     [Serializable, NetSerializable]
-    public class TickerLobbyReadyEvent : EntityEventArgs
+    public sealed class TickerLobbyReadyEvent : EntityEventArgs
     {
         /// <summary>
         /// The Status of the Player in the lobby (ready, observer, ...)
@@ -105,7 +105,7 @@ namespace Content.Shared.GameTicking
     }
 
     [Serializable, NetSerializable]
-    public class TickerJobsAvailableEvent : EntityEventArgs
+    public sealed class TickerJobsAvailableEvent : EntityEventArgs
     {
         /// <summary>
         /// The Status of the Player in the lobby (ready, observer, ...)
@@ -121,7 +121,7 @@ namespace Content.Shared.GameTicking
     }
 
     [Serializable, NetSerializable]
-    public class RoundEndMessageEvent : EntityEventArgs
+    public sealed class RoundEndMessageEvent : EntityEventArgs
     {
         [Serializable, NetSerializable]
         public struct RoundEndPlayerInfo