audit notes work completed, test fixes work (95% done), new sprints, new data sources setup and configuration

src/__Libraries/StellaOps.Doctor.Plugins.Sources/DependencyInjection/SourcesPluginExtensions.cs

@@ -0,0 +1,30 @@
+// -----------------------------------------------------------------------------
+// SourcesPluginExtensions.cs
+// Sprint: SPRINT_20260114_SOURCES_SETUP
+// Task: 12.1 - Sources Doctor Plugin
+// Description: DI extension for registering Sources Doctor Plugin
+// -----------------------------------------------------------------------------
+
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+using StellaOps.Doctor.Plugins;
+
+namespace StellaOps.Doctor.Plugins.Sources.DependencyInjection;
+
+/// <summary>
+/// Extension methods for registering the Sources Doctor plugin.
+/// </summary>
+public static class SourcesPluginExtensions
+{
+    /// <summary>
+    /// Adds the Doctor Sources plugin to the service collection.
+    /// This plugin provides connectivity checks for advisory data sources.
+    /// </summary>
+    /// <param name="services">Service collection.</param>
+    /// <returns>Service collection for chaining.</returns>
+    public static IServiceCollection AddDoctorSourcesPlugin(this IServiceCollection services)
+    {
+        services.TryAddEnumerable(ServiceDescriptor.Singleton<IDoctorPlugin, SourcesPlugin>());
+        return services;
+    }
+}