opt.: use json_serializable

pubspec.yaml

@@ -29,6 +29,7 @@ dependencies:
   wake_on_lan: ^4.1.1+3
   flutter_adaptive_scaffold: ^0.1.10+2
   extended_image: ^8.2.1
+  json_annotation: ^4.9.0
   dartssh2:
     git:
       url: https://github.com/lollipopkit/dartssh2
@@ -77,6 +78,7 @@ dev_dependencies:
   hive_generator: ^2.0.0
   build_runner: ^2.3.2
   flutter_lints: ^3.0.0
+  json_serializable: ^6.8.0
   flutter_test:
     sdk: flutter
   fl_build: