Initial Blazor birth registry app, theming, and services

Implemented a Blazor Web App (.NET 8) for a public-by-link birth registry platform, following project guidelines. Added domain entities, EF Core context, and Blazor components for authentication, registry management, and public views. Introduced core services for registries, theming, user context, platform owner bootstrapping, and SMTP email. Included static assets (Bootstrap, favicon), launch settings, Dockerfile, CI workflow, and deployment configs. Added bootstrap.min.css.map for improved CSS debugging.

src/BirthList.Domain/Entities/Registry.cs

@@ -0,0 +1,21 @@
+namespace BirthList.Domain.Entities;
+
+public class Registry
+{
+    public Guid Id { get; set; }
+    public string PublicLinkCode { get; set; } = string.Empty;
+    public string Title { get; set; } = string.Empty;
+    public DateOnly? BirthDate { get; set; }
+    public string? BabyName { get; set; }
+    public string? HeaderContentHtml { get; set; }
+    public string? ShippingAddress { get; set; }
+    public string CurrencyCode { get; set; } = "EUR";
+    public string ThemeKey { get; set; } = "default";
+    public RegistryType RegistryType { get; set; } = RegistryType.Birth;
+    public DateTimeOffset CreatedAtUtc { get; set; }
+
+    public ICollection<RegistryAdmin> Admins { get; set; } = [];
+    public ICollection<RegistryItem> Items { get; set; } = [];
+    public ICollection<RegistryVisit> Visits { get; set; } = [];
+    public ICollection<RegistryAdminInvite> AdminInvites { get; set; } = [];
+}