controller(card): POST /card/protect

SVSim.EmulatedEntrypoint/Models/Dtos/Responses/Card/CardProtectResponse.cs

@@ -0,0 +1,12 @@
+using MessagePack;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Responses.Card;
+
+/// <summary>
+/// /card/protect response data — empty. The client just needs result_code=1 in the envelope's
+/// data_headers; it mutates its own FavoriteCardList from its request-side knowledge.
+/// </summary>
+[MessagePackObject]
+public class CardProtectResponse
+{
+}