Contacts management.

Wino.Core.Domain/Entities/Shared/AccountContact.cs

@@ -25,7 +25,16 @@ public class AccountContact : IEquatable<AccountContact>
     public string Name { get; set; }
 
     /// <summary>
-    /// Base64 encoded profile image of the contact.
+    /// File ID for the contact picture stored on disk.
+    /// The actual file lives at {ApplicationDataFolderPath}/contacts/{ContactPictureFileId}.jpg.
+    /// Preferred over Base64ContactPicture — allows native BitmapImage file loading and avoids SQLite bloat.
+    /// </summary>
+    public Guid? ContactPictureFileId { get; set; }
+
+    /// <summary>
+    /// Legacy base64 encoded profile image of the contact.
+    /// For user-set contact pictures: migrate to file storage via ContactPictureFileId instead.
+    /// Still used for OAuth account profile pictures (MailAccount.Base64ProfilePictureData).
     /// </summary>
     public string Base64ContactPicture { get; set; }