fix(ch11): Resolve cart initialization bug, stabilize configuration tests, and update Key Vault setup

- Fixed a null reference issue in RefreshShoppingCart() by returning early when the user context is not yet available during first sign-in
- Updated database initialization script to retrieve the connection string from Azure Key Vault
- Updated README to reflect the new Key Vault–based initialization process
- Added .gitignore files to solutions that were missing them
- Excluded the script-generated tenant configuration file from source control
- Refactored configuration integration tests to avoid relying on real application settings
- Replaced Guid.NewGuid() with fixed GUIDs in EF Core seed data where required, since EF cannot translate Guid.NewGuid() during migrations

These changes improve reliability of the sample application, align the database setup with the Key Vault security model introduced in Chapter 11 and later chapters, and ensure tests remain stable as configuration evolves.

Author: cbcrouse

ch09/CleanCart.NET/src/Infrastructure/Persistence/EntityFramework/ProductConfiguration.cs

@@ -18,71 +18,71 @@ public void Configure(EntityTypeBuilder<Product> builder)
         builder.HasData(
             new Product
             {
-                Id = new Guid("f0ae6d4f-a312-4a81-830d-ea0c16131326"),
+                Id = Guid.Parse("f0ae6d4f-a312-4a81-830d-ea0c16131326"),
                 Name = "Wireless Mouse",
                 Price = 29.99m,
                 StockLevel = 150,
                 ImageUrl = "https://placehold.co/200?text=Wireless+Mouse"
             },
             new Product
             {
-                Id = new Guid("543b49a3-2daa-46b3-8498-004322f86f41"),
+                Id = Guid.Parse("543b49a3-2daa-46b3-8498-004322f86f41"),
                 Name = "Mechanical Keyboard",
                 Price = 89.99m,
                 StockLevel = 75,
                 ImageUrl = "https://placehold.co/200?text=Mechanical+Keyboard"
             },
             new Product
             {
-                Id = new Guid("875d83af-a771-4c8b-97e7-c62f2d54b19b"),
+                Id = Guid.Parse("875d83af-a771-4c8b-97e7-c62f2d54b19b"),
                 Name = "27-inch Monitor",
                 Price = 199.99m,
                 StockLevel = 45,
                 ImageUrl = "https://placehold.co/200?text=27-inch+Monitor"
             },
             new Product
             {
-                Id = new Guid("8e8e3c26-2f5a-4ce8-a274-cdc9c83d0b12"),
+                Id = Guid.Parse("8e8e3c26-2f5a-4ce8-a274-cdc9c83d0b12"),
                 Name = "USB-C Hub",
                 Price = 49.99m,
                 StockLevel = 200,
                 ImageUrl = "https://placehold.co/200?text=USB-C+Hub"
             },
             new Product
             {
-                Id = new Guid("ce1bb70b-8faf-4fb5-bac3-8ae488a95beb"),
+                Id = Guid.Parse("ce1bb70b-8faf-4fb5-bac3-8ae488a95beb"),
                 Name = "Noise Cancelling Headphones",
                 Price = 129.99m,
                 StockLevel = 30,
                 ImageUrl = "https://placehold.co/200?text=Noise+Cancelling+Headphones"
             },
             new Product
             {
-                Id = new Guid("91b4da28-d060-43ea-861a-ceb8783ef880"),
+                Id = Guid.Parse("91b4da28-d060-43ea-861a-ceb8783ef880"),
                 Name = "Webcam",
                 Price = 69.99m,
                 StockLevel = 120,
                 ImageUrl = "https://placehold.co/200?text=Webcam"
             },
             new Product
             {
-                Id = new Guid("77b608ae-1ce8-4bb2-b02c-edd4185e54e5"),
+                Id = Guid.Parse("77b608ae-1ce8-4bb2-b02c-edd4185e54e5"),
                 Name = "Portable SSD",
                 Price = 99.99m,
                 StockLevel = 80,
                 ImageUrl = "https://placehold.co/200?text=Portable+SSD"
             },
             new Product
             {
-                Id = new Guid("d182e085-408d-4bc7-aea5-946ca3d0dcec"),
+                Id = Guid.Parse("d182e085-408d-4bc7-aea5-946ca3d0dcec"),
                 Name = "Gaming Chair",
                 Price = 249.99m,
                 StockLevel = 20,
                 ImageUrl = "https://placehold.co/200?text=Gaming+Chair"
             },
             new Product
             {
-                Id = new Guid("7a7d74b7-e9af-41ca-9f89-69c1e7f45c8c"),
+                Id = Guid.Parse("7a7d74b7-e9af-41ca-9f89-69c1e7f45c8c"),
                 Name = "Smart Speaker",
                 Price = 39.99m,
                 StockLevel = 90,

ch09/CleanCart.NET/src/Presentation.BSA/Components/ShoppingCartIcon/ShoppingCartIcon.razor

@@ -68,7 +68,8 @@
 
     private async Task RefreshShoppingCart()
     {
-        _shoppingCart = await ShoppingCartRepository.GetByUserIdAsync(_user!.Id);
+        if (_user is null) return;
+        _shoppingCart = await ShoppingCartRepository.GetByUserIdAsync(_user.Id);
         _isBadgeVisible = _shoppingCart?.Items.Count > 0;
         _cartItemCount = _shoppingCart?.Items.Count ?? 0;
     }