Add settings endpoints and registration status check: implement new API endpoints for settings management, including registration status retrieval, and update the registration command handler to enforce registration rules based on site settings.

backend/src/TeleWave.Infrastructure/DependencyInjection.cs

@@ -14,6 +14,7 @@ using TeleWave.Infrastructure.Broadcast;
 using TeleWave.Infrastructure.Identity;
 using TeleWave.Infrastructure.Media;
 using TeleWave.Infrastructure.Persistence;
+using TeleWave.Infrastructure.Settings;
 using TeleWave.Infrastructure.Streaming;
 
 namespace TeleWave.Infrastructure;
@@ -90,6 +91,7 @@ public static class DependencyInjection
         services.AddScoped<IRefreshTokenService, RefreshTokenService>();
         services.AddScoped<IRoleService, RoleService>();
         services.AddScoped<ICurrentUser, CurrentUser>();
+        services.AddScoped<ISiteSettings, SiteSettings>();
         services.AddScoped<DbInitializer>();
 
         AddMedia(services, configuration);