Delete an event from the user’s calendar. The deletion is written to Google immediately and attendees are notified, so confirm with the user before deleting — it cannot be undone. Get the eventId from ListCalendarEvents. For recurring events, scope controls how much is removed: “all” (default) removes the whole series, “this_event” removes one occurrence, and “this_and_following” ends the series from an occurrence onward. The scoped variants require recurrenceId from the targeted occurrence’s ListCalendarEvents entry.