Introduces BottomSheet and RsvpBar components, integrates the RSVP
submission flow into EventDetailView, extends useEventStorage with
saveRsvp/getRsvp, and adds unit tests plus an E2E spec for the RSVP
workflow.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
New view fetches event via openapi-fetch, formats date/time with
Intl.DateTimeFormat. Skeleton shimmer during loading (CSS-only).
Create form now sends auto-detected timezone.
Unit tests for all five view states, E2E tests with MSW mocks.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
