Lists the email templates of the retailer in the authorizer, newest first by
updatedAt.

Archived templates are excluded unless status=ARCHIVED is asked for explicitly: archiving
is a soft delete and has to disappear from the default listing.

status, category, language, integrationId and title are applied as a DynamoDB
filter, which runs after the limit: a page may come back with fewer items than limit
and still carry a tokenPagination.