cull(engine-cleanup): pass-8 phase-2 cascade round 1

[trim] fully-unreachable files deleted: 6
[trim] files edited: 55, files deleted: 0, nodes removed: 244
[type-trim] files edited: 1, types removed: 1

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

SVSim.BattleEngine/Shim/UnityEngine/UnityShimExt.cs

@@ -32,7 +32,6 @@ namespace UnityEngine
         public bool hasChanged { get; set; }
         public Matrix4x4 localToWorldMatrix => default;
         public Matrix4x4 worldToLocalMatrix => default;
-        public void Rotate(float x, float y) { }
         public void Translate(Vector3 translation, Space relativeTo) { }
         public void Rotate(Vector3 eulers, Space relativeTo) { }
     }
@@ -75,8 +74,6 @@ namespace UnityEngine
 
     public partial class Texture2D
     {
-        public byte[] EncodeToPNG() => Array.Empty<byte>();
-        public bool LoadImage(byte[] data) => false;
     }
 
     public partial class Sprite