cull(engine-cleanup): pass-8 phase-2 cascade round 2

[trim] fully-unreachable files deleted: 3
[trim] files edited: 21, files deleted: 0, nodes removed: 38
[type-trim] files edited: 3, types removed: 3

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

SVSim.BattleEngine/Engine/HandControl.cs

@@ -19,9 +19,7 @@ public abstract class HandControl
 
 	public enum HandVisible
 	{
-		Invisible,
-		Visible
-	}
+		Invisible	}
 
 	protected readonly GameObject _gameObject;