feat: extension support (#78)

ui/flutter/lib/api/model/extension.dart

@@ -0,0 +1,95 @@
+import 'package:json_annotation/json_annotation.dart';
+
+part 'extension.g.dart';
+
+@JsonSerializable(explicitToJson: true)
+class Extension {
+  String identity;
+  String name;
+  String author;
+  String title;
+  String description;
+  String icon;
+  String version;
+  String homepage;
+  Repository? repository;
+  List<Setting>? settings;
+  bool disabled;
+  bool devMode;
+
+  Extension({
+    required this.identity,
+    required this.name,
+    required this.author,
+    required this.title,
+    required this.description,
+    required this.icon,
+    required this.version,
+    required this.homepage,
+    required this.repository,
+    required this.disabled,
+    required this.devMode,
+  });
+
+  factory Extension.fromJson(Map<String, dynamic> json) =>
+      _$ExtensionFromJson(json);
+  Map<String, dynamic> toJson() => _$ExtensionToJson(this);
+}
+
+@JsonSerializable()
+class Repository {
+  String url;
+  String directory;
+
+  Repository({
+    required this.url,
+    required this.directory,
+  });
+
+  factory Repository.fromJson(Map<String, dynamic> json) =>
+      _$RepositoryFromJson(json);
+  Map<String, dynamic> toJson() => _$RepositoryToJson(this);
+}
+
+@JsonSerializable()
+class Setting {
+  String name;
+  String title;
+  String description;
+  bool required;
+  SettingType type;
+  Object? value;
+  List<Option>? options;
+
+  Setting({
+    required this.name,
+    required this.title,
+    required this.description,
+    required this.required,
+    required this.type,
+  });
+
+  factory Setting.fromJson(Map<String, dynamic> json) =>
+      _$SettingFromJson(json);
+  Map<String, dynamic> toJson() => _$SettingToJson(this);
+}
+
+@JsonSerializable()
+class Option {
+  String label;
+  Object value;
+
+  Option({
+    required this.label,
+    required this.value,
+  });
+
+  factory Option.fromJson(Map<String, dynamic> json) => _$OptionFromJson(json);
+  Map<String, dynamic> toJson() => _$OptionToJson(this);
+}
+
+enum SettingType {
+  string,
+  number,
+  boolean,
+}