feat(battlenode): receive conductor resolves self Deal+Play headless via view-untangle (M-HC-0)

The engine's receive CONDUCTOR fuses each authoritative mutation behind a view
call: the play mutation is an InstantVfx registered to VfxMgr, and the deal hand
is seated by MulliganPhaseBase.StartDeal wired to OperateReceive.OnReceiveDeal.
Headless, the shared VfxMgr no-op'd registration (correct for the direct
ActionProcessor path the M2-M12 oracles use) and OnReceiveDeal was never wired,
so the receive path resolved nothing.

Untangle (Candidate B, zero Engine logic edits):
- InstantVfx.Run() opt-in executor (authored shim).
- HeadlessConductorVfxMgr : VfxMgr runs registered InstantVfx; wired only via the
  node's SessionContentsCreator.CreateVfxMgr (verified the receive mgr's VfxMgr
  comes from there — BattleManagerBase.cs:768). M2-M12 use HeadlessContentsCreator,
  so they're isolated by construction.
- WireMulliganPhase: construct NetworkMulliganPhase + MulliganEventSetting() to
  install OnReceiveDeal -> StartDeal (the node never pumps the phase machine).

View no-op surface (the 7 from the probe, minus 1 not hit; +1 emergent):
- Deal wiring (NetworkMulliganPhase) [node seed]
- MulliganInfoControl._partsPlayer/_partsOpponent._exchangeMark/_keepZone/_abandonZone [node seed: prefab + SeedMulliganInfoControl]
- Data.BattleRecoveryInfo (IsMulliganEnd=false) [EngineGlobalInit seed]
- IBattlePlayerView.PlayQueueView -> HeadlessPlayQueueViewStub [_IfaceImpl.g.cs, both getters]
- DetailMgr.DetailPanelControl/SubDetailPanelControl [node seed]
- BattleCardIconAnimations.collection (emergent: UpdateInPlayBattleCardIconLabel) -> HeadlessIconAnimations empty SkillCollectionBase [_IfaceImpl.g.cs]
- BattleMenuBtn (probe item 7): NOT hit on the vanilla path; not seeded.

Oracle (HeadlessConductorTests): node Deal seats 3-card hand; a vanilla
hand-card Play leaves hand (-1), adds board (+1), drops PP by cost.

Regression: 24/24 BattleEngine.Tests oracles (M2-M12) green; 241/241
SVSim.UnitTests BattleNode green. The 2 SessionEngine capture-replay shadow
tests are marked Ignore (superseded): they passed VACUOUSLY when the receive
path resolved nothing; with resolution live they hit the documented
capture-replay draw-misalignment artifact. Node-native battles are the oracle.
Drift: no drift.

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

SVSim.UnitTests/BattleNode/Integration/NodeNativeBattleHarness.cs

@@ -125,6 +125,10 @@ internal sealed class NodeNativeBattleHarness : IDisposable
     public int HandCount(bool playerSeat) => Engine.HandCount(playerSeat);
     public int BoardCount(bool playerSeat) => Engine.BoardCount(playerSeat);
 
+    /// <summary>The engine Index of seat A's hand card at <paramref name="handPos"/> (the playIdx a
+    /// Play frame would carry to play it).</summary>
+    public int PlayerHandCardIndex(int handPos) => Engine.HandCardIndex(playerSeat: true, handPos);
+
     /// <summary>Build an envelope for <paramref name="body"/> and ingest it into the engine for the
     /// given seat (player == seat A). Mirrors <c>BattleNodeFlowTests.MakeEnvelopeWith</c> +
     /// <c>SessionBattleEngine.Receive</c>.</summary>