Event extraction / event parsing — turn any caption, announcement, listing, or page text into a normalized calendar event via Claude Haiku. Resolves relative dates ("this Saturday 7pm") against post time + timezone, handles all-day/multi-day, and returns title, start/end, venue, address, city, price, organizer, url. Purpose-built for structured event data (no schema to define — unlike generic extractors); pairs with /event-classify (cheap filter) and /calendar/ics (publish step).