listContactLists returns a page of list identities and membership counts.
Example
limit defaults to 10 (maximum 50), offset to 0, and sort to desc.
account selects the Brevo binding.
Returns { count, lists }. Each list has positive numeric id and folderId,
name, uniqueSubscribers, and optional totalSubscribers and
totalBlacklisted. Use the ID for stable follow-up references; exact names are
also accepted but fail when duplicated.