listCalendars reads the connected user’s calendar list with provider paging
and incremental sync tokens.
Example
Inputs
OptionalincludeDeleted and includeHidden booleans control list entries.
maxResults accepts 1–250. Use pageToken from a prior page or syncToken
from a completed prior listing. account selects the Google account.
Output
Returns{ calendars: Calendar[]; nextPageToken?: string; nextSyncToken?: string }.
See Get calendar.
The list includes calendars where the account has at least free/busy-reader
access. Follow every page before persisting nextSyncToken.