feat(application): Add EmailProcessedEvent domain event

src/DigitalData.EmailProfiler.Application/Common/Events/OutgoingEmailEvent.cs

@@ -0,0 +1,28 @@
+namespace DigitalData.EmailProfiler.Application.Common.Events;
+
+public class OutgoingEmailEvent
+{
+    public required Guid Id { get; init; }
+
+    /// <summary>
+    /// Recipient email address
+    /// </summary>
+    public required string Recipient { get; init; }
+
+    /// <summary>
+    /// Email subject
+    /// </summary>
+    public required string Subject { get; init; }
+
+    /// <summary>
+    /// Email body (HTML or plain text)
+    /// </summary>
+    public required string Body { get; init; }
+
+    /// <summary>
+    /// Is HTML email (default: true)
+    /// </summary>
+    public bool IsHtml { get; init; } = true;
+
+    public DateTime QueuedAt { get; init; }
+}