ADR 0380: giving a module's own secret now asks the operator channel's
tell over the bus, naming the secret, where, when and who asked, and
raises no secret-given condition. Until nothing serves tell yet, or the
controller's grant is refused (link.ErrNothingServes / the new
link.ErrGrantRefused), the condition is raised exactly as before, so the
change composes whichever side of issue 797 merges first. A successful
tell also retires every open secret-given condition. The terminal's own
secret accept now records a hand act too, as the desk path already did.
The controller's bus grant for operator-channel.tell is added to the
composed config (golden fixture updated).