feat(battle-engine): full Unity/VFX/god-object shims + expanded copy closure (2570 files)

Authored Unity primitive/object-model shim, VFX layer (control-flow-preserving, InstantVfx never invokes its action -- headless suppression), god-object stubs (GameMgr/EffectMgr/UIManager with faithfully-extracted nested enums), View/UI/Touch tree, LitJson+BetterList+Tuple copied, third-party stubs. Discovered Roslyn header-error masking: fixing class-header type errors unmasks body references, so the true copy closure is ~2570 files (was 782 under masking). Errors: masked-25720 -> 268; our shim files compile clean. Remaining: ~50 residual shim/external types, 24 NGUI UI-base overrides, static-type fixes, plus likely 1-2 more unmask waves.

SVSim.BattleEngine/Engine/BattleSettingBaseData.cs

@@ -0,0 +1,36 @@
+using LitJson;
+
+public class BattleSettingBaseData
+{
+	public int PlayerCharaId { get; }
+
+	public int EnemyCharaId { get; }
+
+	public int EnemyClassId { get; }
+
+	public int EnemyAiId { get; }
+
+	public int FieldId { get; }
+
+	public string BgmId { get; }
+
+	public BattleSettingBaseData(JsonData jsonData)
+	{
+		PlayerCharaId = jsonData["chara_id"].ToInt();
+		EnemyCharaId = jsonData["enemy_chara_id"].ToInt();
+		EnemyClassId = jsonData["enemy_class"].ToInt();
+		EnemyAiId = jsonData["enemy_ai_id"].ToInt();
+		FieldId = jsonData["battle3dfield_id"].ToInt();
+		BgmId = GetBgmId(jsonData);
+	}
+
+	private static string GetBgmId(JsonData jsonData)
+	{
+		string text = jsonData["bgm_id"].ToString();
+		if (!(text == "0"))
+		{
+			return text;
+		}
+		return "NONE";
+	}
+}