test(battlenode): N1 shadow replay tracks captured battle state (Phase 2 N1)

Full single-client capture replay (cl1 send=player seat, receive=opponent seat,
ts-ordered) ingests end-to-end: 33 frames, 0 rejects, 0 invariant violations at
turn boundaries (leader life/PP/board/hand).

Headless gaps filled per playbook (no Engine/ drift):
- IsRecovery=true after construction: the engine's own headless replay mode gates
  the live view/UI layer off (BattleUIContainer, turn-control UI, VFX waits) while
  keeping the live NetworkBattleReceiver (ND4) and authoritative state.
- Seed ToolboxGame.RealTimeNetworkAgent, BattleUIContainer, _backGround, and
  per-player NullPlayerEmotion no-ops the receive/turn cycle dereferences.
- _IfaceImpl.g.cs (shim, not Engine/): BattleCardView.BattleCardIconAnimations
  returns a lazy non-null no-op so the opponent card-reveal icon-init (deferred
  VFX) doesn't NRE.
- HeadlessCardMaster.Load made cumulative: it replaced the global CardMaster each
  call, so a Load(deck) evicted the oracle card set and broke tests run after.

Adds board-state accessors (LeaderLife/Pp/HandCount/BoardCount) and CaptureReplay
ts ordering.

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

SVSim.BattleEngine.Tests/HeadlessCardMaster.cs

@@ -19,10 +19,18 @@ namespace SVSim.BattleEngine.Tests
         private static readonly string CardsJsonPath =
             Path.Combine(AppContext.BaseDirectory, "Data", "cards.json");
 
-        // Load the given card ids (empty = none) into a fresh CardMaster registered as Default.
+        // Every id ever requested this process. Load is CUMULATIVE: each call rebuilds the master from
+        // the union, so a later Load(subset) never evicts cards an earlier Load (e.g. EnsureInitialized's
+        // oracle set) installed. Without this, the static CardMaster is shared mutable state across the
+        // whole NUnit run and a Load(deck) in one test silently breaks an oracle test that runs after.
+        private static readonly HashSet<int> _everLoaded = new();
+
+        // Load the given card ids (empty = none) into a CardMaster registered as Default, MERGED with all
+        // previously-loaded ids.
         public static void Load(params int[] cardIds)
         {
-            var want = new HashSet<int>(cardIds);
+            foreach (var id in cardIds) _everLoaded.Add(id);
+            var want = new HashSet<int>(_everLoaded);
             var rows = new List<CardCSVData>();
             if (want.Count > 0)
             {