Prebuilt deck purchasing and fixes

SVSim.EmulatedEntrypoint/Models/Dtos/Responses/LeaderSkin/LeaderSkinSetResponse.cs

@@ -0,0 +1,27 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Responses.LeaderSkin;
+
+/// <summary>
+/// Response shape for POST /leader_skin/set. Per <c>LeaderSkinUpdateTask.Parse</c>:
+///   - <c>is_random_leader_skin</c> echoes the mode the server actually applied.
+///   - <c>leader_skin_id</c> is only consumed by the client when random mode is on (it picks
+///     one of the pool to display). In non-random mode the client uses the request's id.
+///   - <c>leader_skin_id_list</c> is the active shuffle pool (empty for non-random).
+/// </summary>
+[MessagePackObject]
+public class LeaderSkinSetResponse
+{
+    [JsonPropertyName("is_random_leader_skin")]
+    [Key("is_random_leader_skin")]
+    public bool IsRandomLeaderSkin { get; set; }
+
+    [JsonPropertyName("leader_skin_id")]
+    [Key("leader_skin_id")]
+    public int LeaderSkinId { get; set; }
+
+    [JsonPropertyName("leader_skin_id_list")]
+    [Key("leader_skin_id_list")]
+    public List<int> LeaderSkinIdList { get; set; } = new();
+}