feat(pack): gacha-point endpoint DTOs

SVSim.EmulatedEntrypoint/Models/Dtos/GachaPointRewardDetailEntry.cs

@@ -0,0 +1,26 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos;
+
+/// <summary>
+/// One entry inside <c>gacha_point_rewards[i].reward_list</c>. Different shape from the
+/// post-state-totals <see cref="RewardListEntry"/> used by /pack/open: this is a catalog
+/// declaration ("here's what you'd get if you exchanged"), not a viewer-state assignment.
+/// Wire keys verified against prod capture data_dumps/traffic_prod_tradeables_capture.ndjson.
+/// </summary>
+[MessagePackObject]
+public class GachaPointRewardDetailEntry
+{
+    [JsonPropertyName("reward_type")]
+    [Key("reward_type")]
+    public int RewardType { get; set; }
+
+    [JsonPropertyName("reward_detail_id")]
+    [Key("reward_detail_id")]
+    public long RewardDetailId { get; set; }
+
+    [JsonPropertyName("reward_number")]
+    [Key("reward_number")]
+    public int RewardNumber { get; set; } = 1;
+}