First module of floret-kit, the shared Material 3 Expressive design system +
plumbing for the Floret app family. core-time is a pure-Kotlin JVM library
(DayWindow local-day boundaries + locale/zone-aware Instant formatting),
extracted from Agendula. Standalone build + 2 unit tests green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
