Pure advanceStreak (1-day grace none, milestone flags at 3/7/14/30),
persisted in the save blob; StreakNotifier advances on every finished
attempt; home screen flame chip and milestone snackbar. Fix flutter
create's camelCased iOS bundle id and underscored Android application
id to the agreed lowercase form before any store registration.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
SaveRepository (versioned JSON over prefs) with best-result merging and
unlock walking; ContentRepository loads the bundled pack; SeasonFlow/
Progress notifiers orchestrate stage start -> win record -> advance.
Season map grid with stars/locks, Home -> Map -> Game navigation,
close button, next-stage action on the win overlay.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>