feat: enrich gmail correspondence metadata

JobTrackerApi/Controllers/GmailController.cs

@@ -1,4 +1,5 @@
 using System.Security.Claims;
+using System.Text.Json;
 using JobTrackerApi.Data;
 using JobTrackerApi.Models;
 using JobTrackerApi.Services;
@@ -414,12 +415,22 @@ public sealed class GmailController : ControllerBase
         {
             JobApplicationId = job.Id,
             From = isMe ? "Me" : "Company",
+            Direction = isMe ? "outbound" : "inbound",
             Subject = string.IsNullOrWhiteSpace(detail.Subject) ? null : detail.Subject.Trim(),
             Channel = "Email",
             ExternalMessageId = detail.Id,
             ExternalThreadId = string.IsNullOrWhiteSpace(detail.ThreadId) ? null : detail.ThreadId.Trim(),
             ExternalFrom = string.IsNullOrWhiteSpace(detail.From) ? null : detail.From.Trim(),
             ExternalTo = string.IsNullOrWhiteSpace(detail.To) ? null : detail.To.Trim(),
+            ExternalLabelsJson = detail.Labels.Count == 0 ? null : JsonSerializer.Serialize(detail.Labels),
+            AttachmentMetadataJson = detail.Attachments.Count == 0 ? null : JsonSerializer.Serialize(detail.Attachments.Select(attachment => new CorrespondenceAttachmentMetadata
+            {
+                FileName = attachment.FileName,
+                MimeType = attachment.MimeType,
+                SizeBytes = attachment.SizeBytes,
+                GmailAttachmentId = attachment.GmailAttachmentId,
+                Inline = attachment.Inline,
+            })),
             Content = string.IsNullOrWhiteSpace(detail.BodyText) ? detail.Snippet : detail.BodyText,
             Date = messageDate,
         };