Seal/abstract/virtual everything (#6739)

Content.Client/Arcade/BlockGameMenu.cs

@@ -18,7 +18,7 @@ using static Robust.Client.UserInterface.Controls.BoxContainer;
 
 namespace Content.Client.Arcade
 {
-    public class BlockGameMenu : DefaultWindow
+    public sealed class BlockGameMenu : DefaultWindow
     {
         private static readonly Color OverlayBackgroundColor = new(74,74,81,180);
         private static readonly Color OverlayShadowColor = new(0,0,0,83);

Content.Client/Arcade/SpaceVillainArcadeMenu.cs

@@ -7,7 +7,7 @@ using Vector2 = Robust.Shared.Maths.Vector2;
 
 namespace Content.Client.Arcade
 {
-    public class SpaceVillainArcadeMenu : DefaultWindow
+    public sealed class SpaceVillainArcadeMenu : DefaultWindow
     {
         public SpaceVillainArcadeBoundUserInterface Owner { get; set; }
 
@@ -92,7 +92,7 @@ namespace Content.Client.Arcade
             _enemyActionLabel.Text = message.EnemyActionMessage;
         }
 
-        private class ActionButton : Button
+        private sealed class ActionButton : Button
         {
             private readonly SpaceVillainArcadeBoundUserInterface _owner;
             private readonly SharedSpaceVillainArcadeComponent.PlayerAction _playerAction;

Content.Client/Arcade/UI/BlockGameBoundUserInterface.cs

@@ -4,7 +4,7 @@ using Robust.Shared.GameObjects;
 
 namespace Content.Client.Arcade.UI
 {
-    public class BlockGameBoundUserInterface : BoundUserInterface
+    public sealed class BlockGameBoundUserInterface : BoundUserInterface
     {
         private BlockGameMenu? _menu;
 

Content.Client/Arcade/UI/SpaceVillainArcadeBoundUserInterface.cs

@@ -5,7 +5,7 @@ using static Content.Shared.Arcade.SharedSpaceVillainArcadeComponent;
 
 namespace Content.Client.Arcade.UI
 {
-    public class SpaceVillainArcadeBoundUserInterface : BoundUserInterface
+    public sealed class SpaceVillainArcadeBoundUserInterface : BoundUserInterface
     {
         [ViewVariables] private SpaceVillainArcadeMenu? _menu;