Restructures application startup and configuration

Migrates from standalone Program.cs to Startup-based configuration
Adds application configuration JSON for environment-specific settings
Integrates Autofac dependency injection and modular service registration

Configures application services, modules, and middleware for enhanced flexibility

PlanTempus.Components/Outbox/OutboxListenerModule.cs

@@ -1,5 +1,6 @@
 using Autofac;
 using Microsoft.Extensions.Hosting;
+using PlanTempus.Core.Telemetry;
 
 namespace PlanTempus.Components.Outbox;
 
@@ -7,6 +8,10 @@ public class OutboxListenerModule : Module
 {
 	protected override void Load(ContainerBuilder builder)
 	{
+		builder.RegisterType<NotificationChannel>()
+			.As<IMessageChannel<string>>()
+			.SingleInstance();
+
 		builder.RegisterType<OutboxListener>()
 			.As<IHostedService>()
 			.SingleInstance();