feat(sleeve): shop catalog + /sleeve/{info,buy} endpoints

Schema: SleeveShopSeries -> SleeveShopProducts -> Rewards (owned).
Migration AddSleeveShop creates 3 tables with FK cascade.

Importer mirrors BuildDeck pattern: find-or-create per series/product,
rewards replaced wholesale on rerun (owned collection). 10 series,
270 products imported from seeds/sleeve-shop.json.

Controller:
- /sleeve/info returns wire-faithful dict-keyed shape
  ({sleeve_list: {<series_id>: {product_info: {<product_id>: ...}}}}).
  is_purchased_product derived from viewer.Sleeves.Contains(sleeve_id).
- /sleeve/buy: sales_type 0=free / 1=crystal / 2=rupy / 3=ticket(501).
  Validates series_product mismatch, currency, already-purchased.
  Currency debited with post-state-total reward_list entry; cosmetic
  grants dispatched through RewardGrantService.ApplyAsync (covers
  sleeve + emblem bundled grants per product).

476 tests pass (was 466; +10 sleeve tests).

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

SVSim.EmulatedEntrypoint/Models/Dtos/Requests/Sleeve/SleeveBuyRequest.cs

@@ -0,0 +1,25 @@
+using System.Text.Json.Serialization;
+using MessagePack;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Requests;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Requests.Sleeve;
+
+/// <summary>
+/// /sleeve/buy request body. sales_type is ShopCommonUtility.SalesType:
+/// 0=free, 1=crystal, 2=rupy, 3=ticket (v1: 3 returns 501, no ticket-priced sleeve captured).
+/// </summary>
+[MessagePackObject]
+public class SleeveBuyRequest : BaseRequest
+{
+    [JsonPropertyName("series_id")]
+    [Key("series_id")]
+    public int SeriesId { get; set; }
+
+    [JsonPropertyName("product_id")]
+    [Key("product_id")]
+    public int ProductId { get; set; }
+
+    [JsonPropertyName("sales_type")]
+    [Key("sales_type")]
+    public int SalesType { get; set; }
+}