Normalize Activity application architecture

fastlane/metadata/android/en-US/changelogs/66.txt

fastlane/metadata/android/fr-FR/changelogs/66.txt

lib/common/config/activity_page.dart

lib/common/config/screen.dart

lib/common/cubit/nav/nav_cubit_pages.dart

lib/common/cubit/nav/nav_cubit_screens.dart

lib/common/ui/nav/bottom_nav_bar.dart

lib/common/ui/nav/global_app_bar.dart

lib/common/ui/pages/discoveries.dart

lib/common/ui/pages/home.dart

lib/common/ui/pages/statistics.dart

lib/common/ui/screens/about.dart

lib/common/ui/screens/activity.dart

lib/common/ui/screens/settings.dart

lib/common/ui/settings/settings_form.dart

lib/config/application_config.dart

lib/config/default_activity_settings.dart

lib/config/default_global_settings.dart

lib/cubit/activity/activity_cubit.dart

lib/cubit/activity/activity_state.dart