port(m1): wave 7k — M1 COMPLETE: 0 compile errors, headless engine builds (12->0)

Final three clusters:
- RoomParamKey: copy Wizard.RoomMatch/RoomParamKey.cs verbatim (UriNames/WatchUriNames
  static dicts keyed by PlayerController.ROOM_URI + PlayerControllerForWatching.
  SEND_PARAMETER — both now real enums).
- CardChooseTask: copy the TwoPick/CardChooseTask.cs (TaskManager `using`s .Arena.TwoPick,
  not .Competition — copy_loop had only landed the Competition twin).
- SetCardNumLabel CS1739: decompiler param-name artifact — the local fn's 3rd param was
  recovered as `flag` but call sites pass it named `isRed:`. First DP5 tracked patch:
  Engine/UICardList.cs edited (flag->isRed, zero logic change), recorded in
  Patches/ + manifest patched=1 (drift-clean).

M1 exit criteria met: `dotnet build SVSim.BattleEngine` = 0 errors, no Unity ref in csproj,
check_drift clean. Session 7: 198 -> 0 across waves 7a-7k.

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

SVSim.BattleEngine/Engine/Wizard.Scripts.Network.Task.Arena.TwoPick/CardChooseTask.cs

@@ -0,0 +1,39 @@
+using LitJson;
+
+namespace Wizard.Scripts.Network.Task.Arena.TwoPick;
+
+public class CardChooseTask : BaseTask
+{
+	public class ArenaTwoPickCardChooseTaskParam : BaseParam
+	{
+		public int selected_id;
+	}
+
+	public CardChooseTask()
+	{
+		base.type = ApiType.Type.ArenaTwoPickCardChoose;
+	}
+
+	public void SetParameter(int selected_id)
+	{
+		ArenaTwoPickCardChooseTaskParam arenaTwoPickCardChooseTaskParam = new ArenaTwoPickCardChooseTaskParam();
+		arenaTwoPickCardChooseTaskParam.selected_id = selected_id;
+		base.Params = arenaTwoPickCardChooseTaskParam;
+	}
+
+	protected override int Parse()
+	{
+		int num = base.Parse();
+		if (num != 1)
+		{
+			return num;
+		}
+		JsonData jsonData = base.ResponseData["data"];
+		Wizard.Data.TwoPickInfo.SetDeckInfo(jsonData["deck_info"]);
+		if (!Wizard.Data.TwoPickInfo.deckInfo.isSelectCompleted)
+		{
+			Wizard.Data.TwoPickInfo.SetCandidateCardList(jsonData["candidate_card_list"]);
+		}
+		return num;
+	}
+}