v0.3.0

Added

• Multi-language public surfaces (8 locales). The booking page, the manage
  (reschedule/cancel) page, the embed widget, all four emails, the calendar invite
  title/description, and the conversational booking assistant are now translated into
  English, Spanish, French, German, Italian, Portuguese, Dutch and Swedish. The
  locale is negotiated from Accept-Language (so de-AT resolves to de), overridable
  by a footer language switcher (?lang=), with an operator-configurable fallback
  language in Settings → Branding for visitors whose language is not shipped.
• The booker's locale is stored on the booking (migration 00051), so later emails -
  reminders, cancellations, reschedule notices - arrive in the language they booked in
  rather than the language of whoever triggered the send. Host-facing sends stay English.
• Editable assistant greeting (migration 00052) and fallback-language setting
  (migration 00053).
• Adding a language requires no code change - dropping
  internal/i18n/locales/<code>.json in place is the entire task; the switcher, the
  fallback dropdown and the public API payload all read SupportedLocales(). See
  docs/ARCHITECTURE.md §23.

Fixed

• Paid (Stripe) bookings always sent English email regardless of the language the booker
  used, because the confirmation query did not select the stored attendee locale.
• Required checkboxes were not enforced. A custom question of type checkbox marked
  required could be submitted unticked, on both the booking page and the embed widget.
  Now enforced client- and server-side, and the stored answer is canonicalised to
  yes/no instead of varying by surface.
• The public event-type endpoint returned language-dependent content without a Vary
  header, so a shared cache could serve one visitor's language to another.

Notes

• Non-English translations are LLM drafts without native review. Structure is
  verified in CI (key parity, printf-verb parity, and a CLDR cross-check of the date
  tables against Intl); wording is not. Corrections via PR are welcome.
• The built-in video room and the admin UI remain English-only.