updateCalendarAccessRule changes a rule’s role while preserving its scope.
Example
Inputs
ruleId and role are required. Roles are none, freeBusyReader, reader,
writer, or owner. calendar defaults to primary, sendNotifications is
optional, and account selects the Google account.
Output
Returns the updated{ id, role, scope }. The action first reads the existing
rule so its principal cannot accidentally change; create a new rule to change
scope.