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/Shim/Generated/ReplayDataHandler.g.cs

@@ -1,41 +1,9 @@
-// AUTO-GENERATED no-op stubs (m1_stub_gen) from Shadowverse_Code_2026-05-23\Wizard.RoomMatch\ReplayDataHandler.cs
-using System;
-using System.Collections;
-using System.Collections.Generic;
-using System.IO;
-using System.Linq;
-using LitJson;
-using UnityEngine;
+// AUTHORED SHIM (pass-5): ReplayDataHandler kept as minimal no-op subclass of
+// WatchDataHandler. Original auto-generated ctor chained `: base(nBattleMgr, room, ...)`
+// against a 5-arg WatchDataHandler ctor that referenced types (NetworkWatchBattleMgr,
+// RoomConnectController) scheduled for deletion; removed the ctor since nothing
+// constructs `new ReplayDataHandler(...)` anywhere. Methods are the two the
+// (still-live) NewReplayBattleMgr / NetworkReplayBattleMgr call.
 namespace Wizard.RoomMatch
 {
-public partial class ReplayDataHandler
-{
-        private const float WAIT_TIME_SKILL_SELECT_START = 0f;
-        private const float WAIT_TIME_SKILL_SELECT_CARD = 0.5f;
-        private const float WAIT_TIME_SKILL_SELECT_CANCEL = 0.5f;
-        private const float WAIT_TIME_SKILL_SELECT_COMPLETE = 1f;
-        private const float WAIT_TIME_SKILL_CHOICE_START = 0f;
-        private const float WAIT_TIME_SKILL_CHOICE_SELECT = 0.2f;
-        private const float WAIT_TIME_SKILL_CHOICE_CANCEL = 0.5f;
-        private const float WAIT_TIME_SKILL_CHOICE_COMPLETE = 1f;
-        private const float WAIT_TIME_SKILL_FUSION_START = 0.5f;
-        private const float WAIT_TIME_SKILL_FUSION_SELECT = 0.5f;
-        private const float WAIT_TIME_SKILL_FUSION_COMPLETE = 1f;
-        private readonly List<NetworkBattleDefine.NetworkBattleURI> ReplayExceptUriList;
-        private readonly List<NetworkBattleReceiver.ReplayOperationType> _moveTurnConductOperationType;
-        private readonly List<NetworkBattleSender.SELECT_SKILL_OPERATION> notResetForwardReplayOperationList;
-        private NetworkReplayBattleMgr _networkReplayBattleMgr;
-        private JsonData _stockReceiveReplayOperations;
-        private int _operationIndex;
-        public void SetOperationIndex(int index) { }
-        public ReplayDataHandler(NetworkWatchBattleMgr nBattleMgr, RoomConnectController room, float waitTime, bool isNewReplay, string battleId) : base(nBattleMgr, room, waitTime, isNewReplay, battleId) { }
-        protected void Setup(NetworkWatchBattleMgr nBattleMgr, RoomConnectController room, float waitTime) { }
-        public void Stop() { }
-        protected void ParseBattleWatchData(Dictionary<string, object> received) { }
-        protected void CheckConnection() { }
-        protected IEnumerator StockDataPlayer() => default!;
-        private IEnumerator NewStockDataPlayer() => default!;
-        private void ResetForwardReplay(Dictionary<string, object> frontData) { }
-        private float GetWaitTimeForSelectSkill(Dictionary<string, object> frontData) => default!;
-}
 }