refactor(battlenode): close §A boolean-blindness items (MinedToken, Stock, KeyActionType)

Behavior-preserving; 231 BattleNode tests green.

- MinedToken record struct replaces the transpose-prone (int Idx, long CardId,
  CardOwner IsSelf) tuple returned by KnownListBuilder.Mine*. Positional deconstruct
  keeps the Record*From call sites unchanged.
- enum Stock { Normal, Bypass } replaces the negative `bool noStock` on
  IBattleParticipant.PushAsync and DispatchRoute, threaded through both participants,
  BattleSession, and all handler construction sites.
- enum KeyActionType mirrors the client's SendKeyActionDataManager.KeyActionType;
  the StripKeyActionForOpponent guard compares named values, KeyActionEntry.Type is
  the enum (wire-identical via JsonNumberEnumConverter).

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

SVSim.BattleNode/Sessions/Dispatch/Handlers/ForwardWhenBothReadyHandler.cs

@@ -7,7 +7,7 @@ internal sealed class ForwardWhenBothReadyHandler : IFrameHandler
     public IReadOnlyList<DispatchRoute> Handle(FrameDispatchContext ctx)
     {
         if (ctx.BothAfterReady())
-            return new[] { new DispatchRoute(ctx.Other, ctx.Env, false) };
+            return new[] { new DispatchRoute(ctx.Other, ctx.Env, Stock.Normal) };
         return Array.Empty<DispatchRoute>();
     }
 }