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.Bootstrap/Importers/SleeveShopImporter.cs

@@ -0,0 +1,89 @@
+using Microsoft.EntityFrameworkCore;
+using SVSim.Bootstrap.Models.Seed;
+using SVSim.Database;
+using SVSim.Database.Models;
+
+namespace SVSim.Bootstrap.Importers;
+
+/// <summary>
+/// Idempotent upsert of the sleeve-shop catalog from <c>seeds/sleeve-shop.json</c>.
+/// Source is the wire <c>/sleeve/info</c> response, extracted via
+/// <c>data_dumps/extract/extract-sleeve-shop.py</c>. Mirror of the BuildDeck importer pattern.
+/// Rows missing from the seed are LEFT INTACT (so manual test fixtures survive re-runs).
+/// </summary>
+public class SleeveShopImporter
+{
+    public async Task<int> ImportAsync(SVSimDbContext context, string seedDir)
+    {
+        string path = Path.Combine(seedDir, "sleeve-shop.json");
+        var seed = SeedLoader.LoadList<SleeveShopSeriesSeed>(path);
+        if (seed.Count == 0)
+        {
+            Console.WriteLine("[SleeveShopImporter] No seed rows; skipping.");
+            return 0;
+        }
+
+        var existingSeries = await context.SleeveShopSeries
+            .Include(s => s.Products).ThenInclude(p => p.Rewards)
+            .ToDictionaryAsync(s => s.Id);
+
+        int createdSeries = 0, updatedSeries = 0, createdProducts = 0, updatedProducts = 0;
+
+        foreach (var s in seed)
+        {
+            if (s.SeriesId == 0) continue;
+
+            if (!existingSeries.TryGetValue(s.SeriesId, out var series))
+            {
+                series = new SleeveShopSeriesEntry { Id = s.SeriesId };
+                context.SleeveShopSeries.Add(series);
+                existingSeries[s.SeriesId] = series;
+                createdSeries++;
+            }
+            else updatedSeries++;
+
+            series.IsNew = s.IsNew;
+            series.IsEnabled = true;
+
+            var existingProducts = series.Products.ToDictionary(p => p.Id);
+            foreach (var p in s.Products)
+            {
+                if (p.ProductId == 0) continue;
+
+                if (!existingProducts.TryGetValue(p.ProductId, out var product))
+                {
+                    product = new SleeveShopProductEntry { Id = p.ProductId };
+                    series.Products.Add(product);
+                    createdProducts++;
+                }
+                else updatedProducts++;
+
+                product.SeriesId = s.SeriesId;
+                product.NameKey = p.NameKey;
+                product.PriceCrystal = p.PriceCrystal;
+                product.PriceRupy = p.PriceRupy;
+                product.IsEnabled = true;
+
+                // Rewards: replace wholesale (owned collection — EF will issue DELETE+INSERT
+                // anyway, and the wire shape is canonical per re-extract).
+                product.Rewards.Clear();
+                foreach (var r in p.Rewards.OrderBy(r => r.OrderIndex))
+                {
+                    product.Rewards.Add(new SleeveShopProductRewardEntry
+                    {
+                        OrderIndex = r.OrderIndex,
+                        RewardType = r.RewardType,
+                        RewardDetailId = r.RewardDetailId,
+                        RewardNumber = r.RewardNumber,
+                    });
+                }
+            }
+        }
+
+        await context.SaveChangesAsync();
+        Console.WriteLine(
+            $"[SleeveShopImporter] series +{createdSeries}/~{updatedSeries}, " +
+            $"products +{createdProducts}/~{updatedProducts}");
+        return createdSeries + updatedSeries;
+    }
+}