Normalize game architecture

lib/ui/helpers/app_titles.dart

lib/ui/helpers/outlined_text_widget.dart

lib/ui/layouts/game_layout.dart

lib/ui/layouts/parameters_layout.dart

lib/ui/parameters/parameter_image.dart

lib/ui/parameters/parameter_painter.dart

lib/ui/screens/page_about.dart

lib/ui/screens/page_game.dart

lib/ui/screens/page_settings.dart

lib/ui/settings/settings_form.dart

lib/ui/settings/theme_card.dart

lib/ui/skeleton.dart

lib/ui/widgets/actions/button_delete_saved_game.dart

lib/ui/widgets/actions/button_game_quit.dart

lib/ui/widgets/actions/button_game_start_new.dart

lib/ui/widgets/actions/button_resume_saved_game.dart

lib/ui/widgets/game/game_board.dart

lib/ui/widgets/game/game_cell.dart

lib/ui/widgets/game/key.dart

lib/ui/widgets/game/keyboard.dart