refactor(battlenode): engine-first token identity (cardId); keep wire-mining fallback (M-HC-4f, partial)

Source the played card's opponent-facing knownList[].cardId off the shadow engine
(SessionBattleEngine.PlayedCardId -> BattleCardBase.CardId), engine-first with the
wire-mined idx->cardId map as the fallback. PROVEN engine-resolved (each backed by a
HeadlessConductorTests PlayedCardId_* test): deck cards and receive-path substituted/
revealed tokens (engine seats the wire id at the wire idx).

PARTIAL retirement: the wire-mining bookkeeping (MineAddOps/MineChoicePicks/MineCopyTokens
+ Record*From) is KEPT as the load-bearing fallback. The choice/Discover, copy/clone and
cross-side (isSelf:0) token cases are NOT proven to resolve at a wire idx headless — the
autonomous token_draw path seats a chosen token at engine Index 0 (would collide with the
leader), and copy/cross-side aren't cheaply fixturable. Deleting their mining on faith
would silently corrupt opponent reveals, so it stays behind a TODO(M-HC-4f) gate.

- SessionBattleEngine.PlayedCardId: new accessor mirroring PlayedCardClan/Tribe.
- BuildPlayedCard: signature deckMap->explicit cardId; null on cardId==0 (no engine id AND
  no mined/deck-map fallback).
- PlayActionsHandler: cardId = engine.PlayedCardId(seat, idx, fallback: mapped) ; mining retained.
- Tests: PlayedCardId_* (deck/substituted/degrade pass; choice-gap [Explicit] documents the
  Index-0 finding). KnownListBuilder + CaptureConformance call-sites updated to new signature.

Full BattleNode suite 263/263 green; HeadlessConductorTests 27/27; drift clean; no Engine edits.

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

SVSim.UnitTests/BattleNode/Integration/NodeNativeBattleHarness.cs

@@ -242,6 +242,12 @@ internal sealed class NodeNativeBattleHarness : IDisposable
     public int DeckCount(bool playerSeat) => Engine.DeckCount(playerSeat);
     public int Turn(bool playerSeat) => Engine.Turn(playerSeat);
 
+    /// <summary>The engine-resolved wire <c>cardId</c> of the card at engine <paramref name="idx"/> on the
+    /// given seat (M-HC-4f). Pass-through to <c>SessionBattleEngine.PlayedCardId</c> — the TRUE id the engine
+    /// seated (deck id / token id / chosen-token id / copied id), the value the handler now sources for the
+    /// opponent-facing knownList instead of the wire-mined map.</summary>
+    public long PlayedCardId(bool playerSeat, int idx, long fallback = 0) => Engine.PlayedCardId(playerSeat, idx, fallback);
+
     /// <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);