engine cleanup passes 4-7 + multi-instancing ambient rip

Squashes 146 commits from battle-engine-extraction. Net: 2,045 files changed,
+11,896 / -158,687 lines. Ships engine passes 4-7 (dead-code cull, view-layer
stub, receive-path shrink) plus the Phase-5 AsyncLocal ambient deletion that
turns concurrent battles into a type-system property rather than a scope
contract.

## What landed

**Passes 4-7 (chunks 1-34):** Extended the Phase-4 const-false collapse into a
cascading cull across the skill graph, view layer, and receive-path periphery.
Six mode flags (IsWatchBattle/IsReplayBattle/IsAdmin/IsAdminWatch/IsPuzzleQuest/
IsAINetwork) became `const false`, every guarded block deleted. Field*.cs
subclass ctors + BackGroundBase + ObjectChecker culled to no-ops. Mulligan
family reworked to take a mgr param through IMulliganMgr.InitMulligan.
Emotion/Recovery/Resource clusters null-stubbed. Prediction/OperationSimulator/
skill filters converted from static ambient reads to per-mgr reads via
SkillPrm.ownerCard.SelfBattlePlayer.BattleMgr / ins.BattleMgr / this.BattleMgr.

**Phase-5 ambient rip (chunks 35-47):** Deleted BattleAmbient / BattleAmbient-
Context / TestBattleScope in full. Every per-battle mutable slot now lives on
the mgr instance itself:
  mgr.InstanceIsForecast / InstanceIsRandomDraw / InstanceRecoveryInfo /
  InstanceViewerId / InstanceNetworkAgent / GameMgr
BattleManagerBase.GetIns() returns null unconditionally; the residual static
flags + 3 façades (Certification.ViewerId, Data.BattleRecoveryInfo,
ToolboxGame.RealTimeNetworkAgent) are null-tolerant defaults kept for the
handful of engine-internal readers that still reference their types. Zero
BattleAmbient references anywhere in engine + node + tests.

Added pre-seeded GameMgr ctor overload threaded through the mgr chain
(BattleManagerBase → SingleBattleMgr / NetworkBattleManagerBase → NetworkStandard-
BattleMgr → HeadlessBattleMgr / HeadlessNetworkBattleMgr). Fixtures build a
GameMgr, seed it via HeadlessEngineEnv.SeedCharaIds/SeedNetUser, and pass it
to the mgr's ctor — no ambient reach.

Node side (SVSim.BattleNode/SessionBattleEngine): _ctx replaced with a plain
GameMgr field; 34 `using var _ambient = BattleAmbient.Enter(_ctx)` scope wraps
ripped from every accessor and mutator; EngineGlobalInit.WirePerSessionGameMgr
takes GameMgr as a param and runs from SessionBattleEngine.SetupInternal
BEFORE mgr construction.

Test side: TestBattleScope deleted; 18 fixture [SetUp]s migrated to
`HeadlessEngineEnv.EnsureProcessGlobals()`; MultiInstanceEngineTests rewritten
around per-mgr construction (GetIns() → null is the pinned invariant).

## Regression fixes

- **chunk-48** (MulliganCtrl): chunk-35's `= null` stubs on card lookups broke
  the live receive-driven Deal path (BattlePlayerBase.DrawCard NRE'd downstream
  of NetworkPlayerMulliganCtrl.StartMulliganVfx). Restored the three lookups
  via `_battlePlayer.BattleMgr.GetBattleCardIdx`. Engine tests were satisfied
  by the WireMulliganPhase seam; unit tests exposed the live-path gap.

## Ship state

- SVSim.BattleEngine.Tests: 56/56 pass, 2 skip
- SVSim.UnitTests: 1554/1554 pass (was 1523/31-fail before chunk 48)
- Solution build: 0 source warnings (40 pre-existing NU1902 MessagePack CVEs
  in SVSim.EmulatedEntrypoint, unrelated)
- Sequential PVP smoke: verified live (two back-to-back battles, no regression
  on cleanup/spinup)
- Concurrent PVP smoke: verified live

Adds tools/engine-port/ClosureAnalyzer/ — the Roslyn transitive-type-closure
analyzer needed to make future cascade cleanup safe (per feedback memory
"Engine cleanup needs closure tool" from the 2026-06-28 pass-3 failure).

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

SVSim.BattleEngine/Engine/Wizard/PurchaseRewardDialog.cs

@@ -15,14 +15,6 @@ public class PurchaseRewardDialog : MonoBehaviour
 		TITLE_BOTTOM_LARGE_FONT
 	}
 
-	private const int LARGE_FONT_GRID_WIDTH = 275;
-
-	private const float FLICK_MARGIN = 70f;
-
-	private const int CARD_OBJECT_DEPTH = 23;
-
-	private const int CARD_TEXTURE_DEPTH = 21;
-
 	private readonly Vector3 CARDOBJECT_COLLIDER_SIZE = new Vector3(175f, 230f, 1f);
 
 	[SerializeField]
@@ -72,16 +64,6 @@ public class PurchaseRewardDialog : MonoBehaviour
 
 	private Layout _layout;
 
-	private const string PATH_NORMAL_LAYOUT = "UI/layoutParts/Dialog/PurchaseRewardDialog";
-
-	private const string PATH_LAYOUT_10 = "UI/layoutParts/Dialog/PurchaseRewardDialog10";
-
-	private const string PATH_NORMAL_LAYOUT_TITLE_BOTTOM = "UI/layoutParts/Dialog/PurchaseRewardDialogTitleBottom";
-
-	private const string PATH_LAYOUT_10_TITLE_BOTTOM = "UI/layoutParts/Dialog/PurchaseRewardDialog10TitleBottom";
-
-	private const string PATH_LAYOUT_TITLE_BOTTOM_LARGE_FONT = "UI/layoutParts/Dialog/PurchaseRewardDialogTitleBottomLargeFont";
-
 	private bool IsFirstPage => _currentPageIndex <= 1;
 
 	private bool IsLastPage => _currentPageIndex >= _lastPageIndex;
@@ -248,7 +230,7 @@ public class PurchaseRewardDialog : MonoBehaviour
 	{
 		if (!IsFirstPage)
 		{
-			GameMgr.GetIns().GetSoundMgr().PlaySe(Se.TYPE.SYS_SLIDE_BTN);
+
 			ShowPage(_currentPageIndex - 1);
 		}
 	}
@@ -257,7 +239,7 @@ public class PurchaseRewardDialog : MonoBehaviour
 	{
 		if (!IsLastPage)
 		{
-			GameMgr.GetIns().GetSoundMgr().PlaySe(Se.TYPE.SYS_SLIDE_BTN);
+
 			ShowPage(_currentPageIndex + 1);
 		}
 	}
@@ -419,21 +401,4 @@ public class PurchaseRewardDialog : MonoBehaviour
 		}
 		return result;
 	}
-
-	private void OnDestroy()
-	{
-		if (_cardObjList != null)
-		{
-			for (int i = 0; i < _cardObjList.Count; i++)
-			{
-				UnityEngine.Object.Destroy(_cardObjList[i].CardObj.gameObject);
-			}
-			_cardObjList.Clear();
-		}
-		if (_loadedResourceList.Count > 0)
-		{
-			Toolbox.ResourcesManager.RemoveAssetGroup(_loadedResourceList);
-			_loadedResourceList.Clear();
-		}
-	}
 }