Clean/update some code, add "settings" and "about" pages.

android/gradle.properties

assets/translations/en.json

assets/translations/fr.json

fastlane/metadata/android/en-US/changelogs/26.txt

fastlane/metadata/android/fr-FR/changelogs/26.txt

lib/config/default_game_settings.dart

lib/config/menu.dart

lib/cubit/game_cubit.dart

lib/cubit/nav_cubit.dart

lib/cubit/theme_cubit.dart

lib/cubit/theme_state.dart

lib/main.dart

lib/ui/painters/parameter_painter.dart

lib/ui/screens/page_about.dart

lib/ui/screens/page_game.dart

lib/ui/screens/page_settings.dart

lib/ui/skeleton.dart

lib/ui/widgets/button_game_start_new.dart

lib/ui/widgets/game/buttons_yes_no.dart

lib/ui/widgets/game/game.dart