Add "%" on repartition charts, reduce axis titles font size

android/gradle.properties

fastlane/metadata/android/en-US/changelogs/16.txt

fastlane/metadata/android/fr-FR/changelogs/16.txt

lib/ui/widgets/charts/custom_bar_chart.dart

lib/ui/widgets/charts/custom_line_chart.dart

lib/ui/widgets/main_screen/counts_by_day_chart.dart

lib/ui/widgets/main_screen/counts_by_hour_chart.dart

pubspec.yaml