Improve loading charts data

android/gradle.properties

fastlane/metadata/android/en-US/changelogs/33.txt

fastlane/metadata/android/fr-FR/changelogs/33.txt

lib/ui/widgets/app_bar.dart

lib/ui/widgets/card_content.dart

lib/ui/widgets/cards/counts_by_day.dart

lib/ui/widgets/cards/counts_by_hour.dart

lib/ui/widgets/cards/discoveries.dart

lib/ui/widgets/cards/statistics_global.dart

lib/ui/widgets/cards/statistics_recent.dart

lib/ui/widgets/cards/timeline.dart

lib/ui/widgets/cards/top_artists.dart

lib/ui/widgets/update_data.dart

pubspec.yaml