Somewhere between API resources, queue workers, repositories, clients and serializers there is a class of … classes/modules that does the needful. Gun-to-my-head, I would call them “services” but I’m looking for a less overloaded term. Maybe capabilities? Controllers? Pick a term from the business domain? What do you call them?
Perhaps “domain modules” if you want to be more agnostic about the actual shape of the code.