Refactor IEmailQueue to IOutgoingEmailQueue

Renamed the `IEmailQueue` interface to `IOutgoingEmailQueue` to improve clarity and better reflect its purpose as an outgoing email queue. Updated all references to the interface across the codebase, including:

- Replaced `IEmailQueue` with `IOutgoingEmailQueue` in `EmailSenderWorker.cs`.
- Renamed the interface in `IOutgoingEmailQueue.cs`.
- Updated `SendEmailCommandHandler` in `SendEmailCommand.cs` to use `IOutgoingEmailQueue`.
- Modified dependency injection in `DependencyInjection.cs` to register `OutgoingEmailQueue` with `IOutgoingEmailQueue`.
- Updated `OutgoingEmailQueue.cs` to implement `IOutgoingEmailQueue`.

These changes improve code readability, maintainability, and naming consistency.

src/DigitalData.EmailProfiler.API/Workers/EmailSenderWorker.cs

@@ -10,7 +10,7 @@ namespace DigitalData.EmailProfiler.API.Workers;
 /// NO database operations - email account configuration comes from appsettings.
 /// </summary>
 public class EmailSenderWorker(
-    IEmailQueue EmailQueue,
+    IOutgoingEmailQueue EmailQueue,
     ILogger<EmailSenderWorker> Logger,
     IOptions<EmailSenderWorkerConfiguration> configuration) : BackgroundService
 {

src/DigitalData.EmailProfiler.Application/Common/Interfaces/IOutgoingEmailQueue.cs

@@ -6,7 +6,7 @@ namespace DigitalData.EmailProfiler.Application.Common.Interfaces;
 /// <summary>
 /// Email queue interface for outgoing emails.
 /// </summary>
-public interface IEmailQueue
+public interface IOutgoingEmailQueue
 {
     Task EnqueueAsync(OutgoingEmailEvent outgoingEmailEvent, CancellationToken cancellationToken = default);
     Task<OutgoingEmailEvent?> DequeueAsync(CancellationToken cancellationToken = default);

src/DigitalData.EmailProfiler.Application/EmailSending/Commands/SendEmailCommand.cs

@@ -35,7 +35,7 @@ public record SendEmailCommand : IRequest<OutgoingEmailEvent>
 /// Handler for SendEmailCommand
 /// Creates EmailOutbox entity via AutoMapper and enqueues to RabbitMQ
 /// </summary>
-public class SendEmailCommandHandler(IEmailQueue EmailQueue, IMapper Mapper) : IRequestHandler<SendEmailCommand, OutgoingEmailEvent>
+public class SendEmailCommandHandler(IOutgoingEmailQueue EmailQueue, IMapper Mapper) : IRequestHandler<SendEmailCommand, OutgoingEmailEvent>
 {
     public async Task<OutgoingEmailEvent> Handle(SendEmailCommand request, CancellationToken cancellationToken)
     {

src/DigitalData.EmailProfiler.Infrastructure/DependencyInjection.cs

@@ -31,7 +31,7 @@ public static class DependencyInjection
         services.AddSingleton<IEncryptionService, DataProtectionEncryptionService>();
 
         // --- Email Queue (RabbitMQ) ---
-        services.AddSingleton<IEmailQueue, OutgoingEmailQueue>();
+        services.AddSingleton<IOutgoingEmailQueue, OutgoingEmailQueue>();
 
         // --- RabbitMQ Configuration ---
         services.Configure<RabbitMqConfiguration>(

src/DigitalData.EmailProfiler.Infrastructure/Queue/OutgoingEmailQueue.cs

@@ -16,7 +16,7 @@ namespace DigitalData.EmailProfiler.Infrastructure.Queue;
 /// Provides message persistence, scalability, and reliability.
 /// Uses Lazy<T> initialization pattern to avoid blocking constructor.
 /// </summary>
-public class OutgoingEmailQueue : IEmailQueue, IDisposable
+public class OutgoingEmailQueue : IOutgoingEmailQueue, IDisposable
 {
     private readonly ILogger<OutgoingEmailQueue> _logger;
     private readonly RabbitMqConfiguration _config;