feat(leader-skin): shop catalog + 5 endpoints (/products, /buy, /buy_set, /buy_set_item, /ids)

Schema: LeaderSkinShopSeries -> Products (owned rewards) + owned
SetCompletionRewards on the series; ViewerLeaderSkinSetClaim composite
PK (ViewerId, SeriesId) backs the /buy_set_item idempotent-claim check.

Importer mirrors SleeveShopImporter: idempotent find-or-create, owned
collections rewritten wholesale on rerun. 16 series, 104 products.

Controller (extends existing /set with 5 new endpoints):
- /products: dict-keyed-by-series_id-string wire shape. is_completed
  per-viewer, rewards.status from ViewerLeaderSkinSetClaim (0=no set
  sale, 1=available, 2=claimed) matching client RewardStatus enum.
- /buy: single skin, sales_type 1/2 dispatch, 3=>501.
- /buy_set: whole series at SetPrice; requires set_sales_status != 0;
  grants every product's rewards (RewardGrantService idempotent on
  already-owned cosmetics, so partial-set buys don't double-add).
- /buy_set_item: requires viewer owns every skin in series; idempotent
  on re-claim (returns 200 + empty reward_list, not 400) so client
  retries don't error.
- /ids: flat owned-skin-id list for badge refresh.

496 tests pass (was 486; +10 leader-skin-shop tests).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

SVSim.EmulatedEntrypoint/Models/Dtos/Requests/LeaderSkin/LeaderSkinBuyRequest.cs

@@ -0,0 +1,26 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Requests.LeaderSkin;
+
+/// <summary>
+/// /leader_skin/buy request body. sales_type is ShopCommonUtility.SalesType:
+/// 0=free, 1=crystal, 2=rupy, 3=ticket (v1: 3 returns 501 — no ticket-priced skin captured).
+/// <see cref="ItemId"/> is the ticket item id when paying with a ticket, null otherwise.
+/// </summary>
+[MessagePackObject]
+public class LeaderSkinBuyRequest : BaseRequest
+{
+    [JsonPropertyName("product_id")]
+    [Key("product_id")]
+    public int ProductId { get; set; }
+
+    [JsonPropertyName("sales_type")]
+    [Key("sales_type")]
+    public int SalesType { get; set; }
+
+    [JsonPropertyName("item_id")]
+    [Key("item_id")]
+    public long? ItemId { get; set; }
+}

SVSim.EmulatedEntrypoint/Models/Dtos/Requests/LeaderSkin/LeaderSkinBuySetItemRequest.cs

@@ -0,0 +1,18 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Requests.LeaderSkin;
+
+/// <summary>
+/// /leader_skin/buy_set_item — claim the series-completion bonus once every skin in the series
+/// is owned. <c>sales_type</c> field exists on the client's param class but is never set; server
+/// ignores it.
+/// </summary>
+[MessagePackObject]
+public class LeaderSkinBuySetItemRequest : BaseRequest
+{
+    [JsonPropertyName("series_id")]
+    [Key("series_id")]
+    public int SeriesId { get; set; }
+}

SVSim.EmulatedEntrypoint/Models/Dtos/Requests/LeaderSkin/LeaderSkinBuySetRequest.cs

@@ -0,0 +1,24 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Requests.LeaderSkin;
+
+/// <summary>
+/// /leader_skin/buy_set — purchase every skin in a series in one call (cheaper per-skin).
+/// </summary>
+[MessagePackObject]
+public class LeaderSkinBuySetRequest : BaseRequest
+{
+    [JsonPropertyName("series_id")]
+    [Key("series_id")]
+    public int SeriesId { get; set; }
+
+    [JsonPropertyName("sales_type")]
+    [Key("sales_type")]
+    public int SalesType { get; set; }
+
+    [JsonPropertyName("item_id")]
+    [Key("item_id")]
+    public long? ItemId { get; set; }
+}

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

@@ -0,0 +1,18 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Responses.LeaderSkin;
+
+/// <summary>
+/// /leader_skin/buy, /leader_skin/buy_set, /leader_skin/buy_set_item all return the same shape:
+/// a <c>reward_list</c> of standard <see cref="RewardListEntry"/> entries (post-state totals
+/// for currencies, grant counts for cosmetics).
+/// </summary>
+[MessagePackObject]
+public class LeaderSkinBuyResponse
+{
+    [JsonPropertyName("reward_list")]
+    [Key("reward_list")]
+    public List<RewardListEntry> RewardList { get; set; } = new();
+}

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

@@ -0,0 +1,16 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Responses.LeaderSkin;
+
+/// <summary>
+/// /leader_skin/ids — flat list of leader_skin_ids the viewer owns. Used by the client to
+/// refresh badges across the skin-selection UI without re-fetching the full shop catalog.
+/// </summary>
+[MessagePackObject]
+public class LeaderSkinIdsResponse
+{
+    [JsonPropertyName("user_leader_skin_ids")]
+    [Key("user_leader_skin_ids")]
+    public List<int> UserLeaderSkinIds { get; set; } = new();
+}

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

@@ -0,0 +1,181 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Responses.LeaderSkin;
+
+// /leader_skin/products wire shape: `data` IS the per-series dict (no wrapping field).
+// Per SkinPurchaseInfoTask.Parse line 31: `JsonData jsonData = base.ResponseData["data"];`
+// then iterates positionally. Dict-keyed-by-series_id_string mirrors the prod capture exactly.
+// The controller returns Dictionary<string, SkinSeriesDto> directly so `data` becomes that dict.
+
+[MessagePackObject]
+public class SkinSeriesDto
+{
+    [JsonPropertyName("series_id")]
+    [Key("series_id")]
+    public int SeriesId { get; set; }
+
+    /// <summary>True when the viewer owns every product's skin in this series.</summary>
+    [JsonPropertyName("is_completed")]
+    [Key("is_completed")]
+    public bool IsCompleted { get; set; }
+
+    [JsonPropertyName("is_new")]
+    [Key("is_new")]
+    public bool IsNew { get; set; }
+
+    /// <summary>Always emit — client unconditionally calls .ToInt() on this field.</summary>
+    [JsonPropertyName("set_sales_status")]
+    [Key("set_sales_status")]
+    public int SetSalesStatus { get; set; }
+
+    [JsonPropertyName("rewards")]
+    [Key("rewards")]
+    public SkinSeriesRewardsDto Rewards { get; set; } = new();
+
+    /// <summary>Always emit — client reads this dict when set_sales_status != 0.</summary>
+    [JsonPropertyName("set_prices")]
+    [Key("set_prices")]
+    public SkinSeriesSetPricesDto SetPrices { get; set; } = new();
+
+    [JsonPropertyName("sales_period_info")]
+    [Key("sales_period_info")]
+    public List<object> SalesPeriodInfo { get; set; } = new();
+
+    [JsonPropertyName("products")]
+    [Key("products")]
+    public List<SkinProductDto> Products { get; set; } = new();
+}
+
+[MessagePackObject]
+public class SkinSeriesRewardsDto
+{
+    /// <summary>SkinSeriesPurchaseInfo.RewardStatus — 0=none, 1=not_got, 2=got.</summary>
+    [JsonPropertyName("status")]
+    [Key("status")]
+    public int Status { get; set; }
+
+    [JsonPropertyName("items")]
+    [Key("items")]
+    public List<SkinSeriesRewardItemDto> Items { get; set; } = new();
+}
+
+[MessagePackObject]
+public class SkinSeriesRewardItemDto
+{
+    [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; }
+}
+
+[MessagePackObject]
+public class SkinSeriesSetPricesDto
+{
+    [JsonPropertyName("set_price_crystal")]
+    [Key("set_price_crystal")]
+    public int? SetPriceCrystal { get; set; }
+
+    [JsonPropertyName("set_price_rupy")]
+    [Key("set_price_rupy")]
+    public int? SetPriceRupy { get; set; }
+
+    [JsonPropertyName("set_price_ticket")]
+    [Key("set_price_ticket")]
+    public int? SetPriceTicket { get; set; }
+
+    [JsonPropertyName("ticket_id")]
+    [Key("ticket_id")]
+    public long? TicketId { get; set; }
+}
+
+[MessagePackObject]
+public class SkinProductDto
+{
+    [JsonPropertyName("product_id")]
+    [Key("product_id")]
+    public int ProductId { get; set; }
+
+    [JsonPropertyName("leader_skin_id")]
+    [Key("leader_skin_id")]
+    public int LeaderSkinId { get; set; }
+
+    [JsonPropertyName("product_name")]
+    [Key("product_name")]
+    public string ProductName { get; set; } = string.Empty;
+
+    [JsonPropertyName("introduction")]
+    [Key("introduction")]
+    public string Introduction { get; set; } = string.Empty;
+
+    [JsonPropertyName("cv_name")]
+    [Key("cv_name")]
+    public string CvName { get; set; } = string.Empty;
+
+    [JsonPropertyName("is_purchased")]
+    [Key("is_purchased")]
+    public bool IsPurchased { get; set; }
+
+    [JsonPropertyName("sale")]
+    [Key("sale")]
+    public SkinProductSaleDto Sale { get; set; } = new();
+
+    [JsonPropertyName("sales_period_info")]
+    [Key("sales_period_info")]
+    public List<object> SalesPeriodInfo { get; set; } = new();
+
+    [JsonPropertyName("rewards")]
+    [Key("rewards")]
+    public List<SkinProductRewardDto> Rewards { get; set; } = new();
+}
+
+[MessagePackObject]
+public class SkinProductSaleDto
+{
+    [JsonPropertyName("single_price_crystal")]
+    [Key("single_price_crystal")]
+    public int? SinglePriceCrystal { get; set; }
+
+    [JsonPropertyName("single_price_rupy")]
+    [Key("single_price_rupy")]
+    public int? SinglePriceRupy { get; set; }
+
+    [JsonPropertyName("single_price_ticket")]
+    [Key("single_price_ticket")]
+    public int? SinglePriceTicket { get; set; }
+
+    [JsonPropertyName("ticket_number")]
+    [Key("ticket_number")]
+    public int? TicketNumber { get; set; }
+
+    [JsonPropertyName("item_id")]
+    [Key("item_id")]
+    public long? ItemId { get; set; }
+}
+
+[MessagePackObject]
+public class SkinProductRewardDto
+{
+    [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; }
+
+    [JsonPropertyName("is_owned")]
+    [Key("is_owned")]
+    public bool IsOwned { get; set; }
+}