test: repair test suite broken by feature drift (red -> 81 passing)

The test project no longer compiled: recent feature commits changed
interfaces and DTOs without updating the test doubles/call sites, so the
whole suite (and therefore CI) was failing to build.

- NoOpInventoryService: add IInventoryService.GetPurchasesSummaryAsync and
  the new string? userId param on AdjustAsync.
- NoOpLoyaltyService: add ILoyaltyService.RedeemOnOrderAsync.
- NoOpOrderNotificationService: add NotifyCallWaiterAsync.
- New NoOpAbuseProtectionService and NoOpMediaStorageService test doubles.
- QrMenuTests: ReviewService/PublicService gained IAbuseProtectionService +
  IHttpContextAccessor (and ReviewService an IMediaStorageService); wire the
  new no-op doubles + a real HttpContextAccessor.
- PrintingTests: OrderDto gained a DisplayNumber int between CreatedAt and
  Items; pass it.
- DiscoverFilterTests: add missing `using Xunit;` and the new openNow arg on
  DiscoverFilterParams.FromQuery.

Result: dotnet test -> Passed: 81, Failed: 0.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

tests/Meezi.API.Tests/NoOpInventoryService.cs

@@ -16,9 +16,17 @@ internal sealed class NoOpInventoryService : IInventoryService
     public Task<IngredientDto?> UpdateAsync(string cafeId, string ingredientId, UpdateIngredientRequest request, CancellationToken ct = default) =>
         Task.FromResult<IngredientDto?>(null);
 
-    public Task<IngredientDto?> AdjustAsync(string cafeId, string ingredientId, AdjustStockRequest request, CancellationToken ct = default) =>
+    public Task<IngredientDto?> AdjustAsync(string cafeId, string ingredientId, AdjustStockRequest request, string? userId, CancellationToken ct = default) =>
         Task.FromResult<IngredientDto?>(null);
 
+    public Task<InventoryPurchasesSummaryDto> GetPurchasesSummaryAsync(
+        string cafeId,
+        string branchId,
+        DateOnly from,
+        DateOnly to,
+        CancellationToken ct = default) =>
+        Task.FromResult(new InventoryPurchasesSummaryDto(0, 0, []));
+
     public Task<MenuItemRecipeDto?> GetRecipeAsync(string cafeId, string menuItemId, CancellationToken ct = default) =>
         Task.FromResult<MenuItemRecipeDto?>(null);