feat: migrate shared_preferences to hive (#343)

ui/flutter/lib/database/entity.dart

@@ -0,0 +1,37 @@
+import 'package:json_annotation/json_annotation.dart';
+
+part 'entity.g.dart';
+
+@JsonSerializable()
+class StartConfigEntity {
+  String network;
+  String address;
+  String apiToken;
+
+  StartConfigEntity({
+    required this.network,
+    required this.address,
+    required this.apiToken,
+  });
+
+  factory StartConfigEntity.fromJson(Map<String, dynamic> json) =>
+      _$StartConfigEntityFromJson(json);
+  Map<String, dynamic> toJson() => _$StartConfigEntityToJson(this);
+}
+
+@JsonSerializable()
+class WindowStateEntity {
+  bool? isMaximized;
+  double? width;
+  double? height;
+
+  WindowStateEntity({
+    this.isMaximized,
+    this.width,
+    this.height,
+  });
+
+  factory WindowStateEntity.fromJson(Map<String, dynamic> json) =>
+      _$WindowStateEntityFromJson(json);
+  Map<String, dynamic> toJson() => _$WindowStateEntityToJson(this);
+}