feat(battle-engine-port): M3 COMPLETE — fixed-damage spell resolves headless (leader-life-delta oracle passes)

Card 900124030 (ELF cost-3, when_play damage=3 to enemy leader) resolves to
correct authoritative state headless via the IsForecast/IsRecovery +
ActionProcessor.PlayCard path. New oracle dimension (opponent leader-life delta)
passes; 3/3 tests green; engine still 0 errors; check_drift clean.

Four headless gaps, each mechanical (no logic/Unity wall):
- Data seam: InitLeaderLife (SetupInitialGameState->InitializeClassLife subset);
  leader BaseMaxLife was 0 => game-over => play silently rejected. M2 missed it
  (only asserted leader life unchanged: 0==0).
- Runtime cast: re-attach IClassBattleCardView on the generated
  NullClassBattleCardView stub (members already present; base-clause recovery
  stripped the decl). Compiled fine -> M1 loop never surfaced it.
- M1 mis-cut: copy NullVfxWithLoading verbatim (its GetInstance() lazy singleton
  was stubbed to default!/null). Same pattern as M2 NullCardVfxCreator.
- Card events: CreateHeadlessHandCard now calls SetupCardEvent so a spell's
  OnPlay->RemoveSpellCardFromHand / OnFinishWhenPlaySkill->AddSpellCardToCemetery
  fire (the bare CreateCardWithoutResources seam skips them).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

SVSim.BattleEngine/COPIED.manifest.tsv

@@ -3311,3 +3311,4 @@ llField.cs	llField.cs	a0e0eaed3f22a8c4ce47f82fa80346e3b99e3ac0a6765e1ad4ade3a87c
 Wizard.Battle.View/CardIconControl.cs	Wizard.Battle.View/CardIconControl.cs	affd5a289a04bc9f446f3e892403dd9cd560ee557de1e5cd743dcb031dab280c	0
 Wizard.Battle.View.Vfx/NullCardVfxCreator.cs	Wizard.Battle.View.Vfx/NullCardVfxCreator.cs	bf8f34d27f41df0dc728c47f874465869649299a5195c2d616597d7a37c581f5	0
 Wizard.Battle.View.Vfx/NotEmptyNullVfx.cs	Wizard.Battle.View.Vfx/NotEmptyNullVfx.cs	fd471e4254bde6dded2c1447714e605a9889b97b01a834bc616585bcff738825	0
+Wizard.Battle.View.Vfx/NullVfxWithLoading.cs	Wizard.Battle.View.Vfx/NullVfxWithLoading.cs	c297c7c7e53fc9a41e46b5f52baa65f905bc51943d6a0fbe683a98fc0668b9b9	0

SVSim.BattleEngine/Engine/Wizard.Battle.View.Vfx/NullVfxWithLoading.cs

@@ -0,0 +1,36 @@
+using System.Collections.Generic;
+
+namespace Wizard.Battle.View.Vfx;
+
+public class NullVfxWithLoading : VfxWithLoading
+{
+	private static NullVfxWithLoading _instance;
+
+	public override VfxBase LoadingVfx => NullVfx.GetInstance();
+
+	public override VfxBase MainVfx => NullVfx.GetInstance();
+
+	public override bool IsEnd => true;
+
+	public static NullVfxWithLoading GetInstance()
+	{
+		if (_instance == null)
+		{
+			_instance = new NullVfxWithLoading();
+		}
+		return _instance;
+	}
+
+	public override void Play()
+	{
+	}
+
+	public override void Update(float dt, List<IEffectVfx> effectVfxList)
+	{
+	}
+
+	public override bool IsVfxNonEmpty()
+	{
+		return false;
+	}
+}

SVSim.BattleEngine/Shim/Generated/NullVfxWithLoading.g.cs

@@ -1,16 +0,0 @@
-// AUTO-GENERATED no-op stubs (m1_stub_gen) from Shadowverse_Code_2026-05-23\Wizard.Battle.View.Vfx\NullVfxWithLoading.cs
-using System.Collections.Generic;
-namespace Wizard.Battle.View.Vfx
-{
-public partial class NullVfxWithLoading
-{
-        private static NullVfxWithLoading _instance;
-        public VfxBase LoadingVfx { get; set; }
-        public VfxBase MainVfx { get; set; }
-        public bool IsEnd { get; set; }
-        public static NullVfxWithLoading GetInstance() => default!;
-        public void Play() { }
-        public void Update(float dt, List<IEffectVfx> effectVfxList) { }
-        public bool IsVfxNonEmpty() => default!;
-}
-}

SVSim.BattleEngine/Shim/Generated/_BaseClauses.g.cs

@@ -101,7 +101,6 @@ namespace Wizard.Battle.View { public partial class NullClassBattleCardView : Nu
 namespace Wizard.Battle.View { public partial class NullEnemyBattleView : BattleEnemyView { } }
 namespace Wizard.Battle.View { public partial class NullFieldBattleCardView : FieldBattleCardView { } }
 namespace Wizard.Battle.View { public partial class NullPlayerBattleView : BattlePlayerView { } }
-namespace Wizard.Battle.View.Vfx { public partial class NullVfxWithLoading : VfxWithLoading { } }
 namespace Wizard.Battle.View.Vfx { public partial class OneShotHeavenlyAegisPlayVfx : SequentialVfxPlayer { } }
 namespace Wizard.Battle.View.Vfx { public partial class OpenCardFromHandVfx : SequentialVfxPlayer { } }
 namespace Wizard.Battle.View.Vfx { public partial class OpenCardVfx : SequentialVfxPlayer { } }

SVSim.BattleEngine/Shim/View/SettingsUiStubs.cs

@@ -61,6 +61,16 @@ namespace Wizard.Battle.View
         public virtual void ClearSpineObject() { }
     }
     public class NullBattleCardView : BattleCardView { public NullBattleCardView() { } public NullBattleCardView(BuildInfo buildInfo) { } public static void ReleaseSharedDummy() { } }
+
+    // The decomp NullClassBattleCardView is `: NullBattleCardView, IClassBattleCardView, IBattleCardView`;
+    // base-clause recovery kept only the base class. IBattleCardView is satisfied via the BattleCardView
+    // base, but IClassBattleCardView was dropped. The generated NullClassBattleCardView stub already
+    // provides that interface's members (public no-ops), so just re-attach the dropped interface here.
+    // The resolution path's VirtualClone (createNullView) -> ClassBattleCardBase.Setup casts the null
+    // view to IClassBattleCardView, which throws InvalidCastException at runtime without this (M3,
+    // fixed-damage spell: Skill_damage.TakeDamageSingle clones the leader before applying damage).
+    // Compiles fine without it (it's a cast, not a member call), so the M1 loop never surfaced it.
+    public partial class NullClassBattleCardView : IClassBattleCardView { }
 }
 
 namespace Wizard.Battle.View.Vfx