feat(combat): serialize RemoveSelectedStatusNode via CombatJson (#2)

Registers node.removeSelectedStatus so a status-instance-targeting program
round-trips (selector + StatusSelectionSpec via existing converters). The op is
now data-authorable end to end.

Author: Paranoidgrinch

src/RogueDeck.Core/Combat/Serialization/CombatJson.cs

@@ -238,6 +238,7 @@ private static void RegisterNodes(CombatJsonRegistry r)
          .Register("node.applyStatus", typeof(ApplyStatusNode<>))
          .Register("node.removeStatus", typeof(RemoveStatusNode<>))
          .Register("node.removeStatusesByPolarity", typeof(RemoveStatusesByPolarityNode<>))
+         .Register("node.removeSelectedStatus", typeof(RemoveSelectedStatusNode<>))
          .Register("node.modifyStatusStacks", typeof(ModifyStatusStacksNode<>))
          .Register("node.modifyStatusDuration", typeof(ModifyStatusDurationNode<>))
          .Register("node.modifyStatusCharges", typeof(ModifyStatusChargesNode<>))

tests/RogueDeck.Core.Tests/CombatJsonBroadNodeTests.cs

@@ -44,6 +44,10 @@ public void Status_and_card_nodes_round_trip()
         var burn = new StatusDefinitionId("burn");
         RoundTrips(new RemoveStatusNode<CardPlayContext>(Enemy, burn));
         RoundTrips(new RemoveStatusesByPolarityNode<CardPlayContext>(Source, StatusPolarity.Debuff));
+        RoundTrips(new RemoveSelectedStatusNode<CardPlayContext>(Enemy,
+            new StatusSelectionSpec(StatusPolarityFilter.Buff, StatusPick.Random)));
+        RoundTrips(new RemoveSelectedStatusNode<CardPlayContext>(Enemy,
+            new StatusSelectionSpec(StatusPolarityFilter.Debuff, StatusPick.First, Index: 2)));
         RoundTrips(new ModifyStatusStacksNode<CardPlayContext>(Enemy, burn, Const(2)));
         RoundTrips(new ModifyStatusDurationNode<CardPlayContext>(Enemy, burn, Const(1)));
         RoundTrips(new ModifyStatusChargesNode<CardPlayContext>(Enemy, burn, Const(1)));