feat(api): .NET 10 multi-tenant REST API

Full backend implementation:
- Multi-tenant cafe/restaurant management (menus, orders, tables, staff)
- POS order flow with ZarinPal and Snappfood payment integration
- OTP authentication via Kavenegar SMS
- QR digital menu with public discover/finder endpoints
- Customer loyalty, coupons, CRM
- PostgreSQL via EF Core, Redis for caching/sessions
- Background jobs, webhook handlers
- Full migration history

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

tests/Meezi.API.Tests/NoOpInventoryService.cs

@@ -0,0 +1,34 @@
+using Meezi.API.Services;
+
+namespace Meezi.API.Tests;
+
+internal sealed class NoOpInventoryService : IInventoryService
+{
+    public Task<IReadOnlyList<IngredientDto>> ListAsync(string cafeId, CancellationToken ct = default) =>
+        Task.FromResult<IReadOnlyList<IngredientDto>>([]);
+
+    public Task<IReadOnlyList<IngredientDto>> LowStockAsync(string cafeId, CancellationToken ct = default) =>
+        Task.FromResult<IReadOnlyList<IngredientDto>>([]);
+
+    public Task<IngredientDto?> CreateAsync(string cafeId, CreateIngredientRequest request, CancellationToken ct = default) =>
+        Task.FromResult<IngredientDto?>(null);
+
+    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) =>
+        Task.FromResult<IngredientDto?>(null);
+
+    public Task<MenuItemRecipeDto?> GetRecipeAsync(string cafeId, string menuItemId, CancellationToken ct = default) =>
+        Task.FromResult<MenuItemRecipeDto?>(null);
+
+    public Task<MenuItemRecipeDto?> SetRecipeAsync(string cafeId, string menuItemId, SetMenuItemRecipeRequest request, CancellationToken ct = default) =>
+        Task.FromResult<MenuItemRecipeDto?>(null);
+
+    public Task<OrderDeductionResult> DeductForOrderAsync(
+        string cafeId,
+        string orderId,
+        IReadOnlyList<(string MenuItemId, int Quantity)> lines,
+        CancellationToken ct = default) =>
+        Task.FromResult(new OrderDeductionResult(false, []));
+}