Helpers work in local Work profiles, and stop with their chat
Helpers started from a Work profile on a model on this Mac now run on that model, and stopping a chat also stops its local Rack calls.
A helper started from a chat whose Work profile runs on a model on this Mac used to say its model was unavailable. It now runs on that same model, with the profile's context limit.
Stopping one chat now also stops the Rack calls it started on this Mac: ranking, recall, image descriptions and drawings. Other chats keep theirs running.