Raised by Kino.Qx.run/2,3 and Kino.Qx.run!/2,3 when the caller
cell process is interrupted via Livebook's trappable "Stop"
(:shutdown) while a hardware run is in flight.
Before raising, the caller issues a best-effort
Qx.Hardware.cancel/3 for any in-flight job (the :job_id field
carries the last-seen job id, or nil if no job had started yet).
This exception is not raised on the untrappable :kill path:
there the caller dies immediately and the unlinked cancel watcher
is the only line of defence — cancel is attempted but no exception
surfaces because the process is already gone. See
Kino.Qx.Run's "Interrupt semantics" for the full contract.