Stop sharing an app connection with a workspace, or take back one API key's grant [write]

app:<slug> only (422 not_shareable otherwise); the same fields as sharing, in the query. Without api_key, workspace's sessions lose your connection of that app at once, as DELETE /universes/{slug}/connections/{id}. With api_key (a key id of the request's workspace, which workspace must name), that key can no longer call through it, as DELETE /connectors/connections/{id}/grants; all_api_keys=true takes back the grant to every key of that workspace. The connection itself stays connected. connection_id when you have several (else 409 connection_required); a workspace owner or admin may name another member's connection shared with workspace. 404 when it was not shared there. A workspace key is 403 person_required.