TF-106 Fix display inlined image CIDs of emails

model/lib/extensions/list_attachment_extension.dart

@@ -0,0 +1,23 @@
+import 'package:model/model.dart';
+
+extension ListAttachmentExtension on List<Attachment> {
+
+  num totalSize() {
+    num totalSize = 0;
+    forEach((attachment) {
+      if (attachment.size != null) {
+        totalSize += attachment.size!.value;
+      }
+    });
+    return totalSize;
+  }
+
+  List<Attachment> get attachmentsWithDispositionAttachment {
+    return where((attachment) => attachment.disposition == ContentDisposition.attachment).toList();
+  }
+
+  List<Attachment> get attachmentWithDispositionInlines {
+    return where((attachment) => attachment.disposition == ContentDisposition.inline && attachment.cidNotEmpty())
+      .toList();
+  }
+}