Contact support without an account

Runs support.guestCreateTicket (public). For a signed-out guest — typically one who booked without an account (critical decision #4). Stores the ticket against email and returns only { publicId }: the link to read and reply to the thread is emailed to that address, so opening it proves the guest owns the inbox. The response is the same whether or not an account uses that email. Signed-in callers get 400 and must use POST /v1/support/tickets. Rate limited to 5 tickets per 10 minutes per IP and 3 per email address per hour (429). Native callers send no Turnstile token. locale picks the email language and falls back to English.