⚡ Optimize post attachment loading

lib/models/post.dart

@@ -1,10 +1,19 @@
 import 'package:json_annotation/json_annotation.dart';
 import 'package:solian/models/account.dart';
+import 'package:solian/models/attachment.dart';
 import 'package:solian/models/post_categories.dart';
 import 'package:solian/models/realm.dart';
 
 part 'post.g.dart';
 
+class PostPreload {
+  List<Attachment> attachments;
+
+  PostPreload({
+    required this.attachments,
+  });
+}
+
 @JsonSerializable()
 class Post {
   int id;
@@ -33,6 +42,9 @@ class Post {
   Account author;
   PostMetric? metric;
 
+  @JsonKey(includeFromJson: false, includeToJson: false)
+  PostPreload? preload;
+
   Post({
     required this.id,
     required this.createdAt,