List the calendars the user can see across their connected inboxes, with each calendar’s calendarId, display name, owning inbox address, and whether it is primary and writable. Use this before CreateCalendarEvent when the user wants an event on a specific non-default calendar (e.g. “add it to my work calendar”) so you can pass the exact calendarId. Most users have a single primary calendar, in which case CreateCalendarEvent targets it by default and you do not need this tool. An empty result means no calendar is connected.