Client Instances Are Actors, Not New Clients
Client instances are not new clients. They are actors. With the Actor Profile and RFC 8693’s actor_token wire already in place, and an instance_issuers field that fits any client registration channel (static, Dynamic Client Registration, or CIMD), treating instances as first-class actors needs no new grant type, no new client type, and no new claim. It needs a profile that ties them together.