- attempt_needs_retry checked .result type, but the envelope's result is a
  plain text message even on success — the structured business result lives
  in .structured_output. Every healthy run was therefore misjudged and
  silently re-run (attempt2 all_seen fast-exits made it cheap and invisible;
  reuters-technology went to attempt3 and was then killed by a schedule
  reload). Criterion now: rc!=0 / empty / invalid JSON / structured_output
  not an object / is_error.
- modify-source.sh refuses to reload a schedule while the source (site)
  has a live harvest runlock — launchctl bootout terminates the running
  job (exactly what killed reuters-technology attempt3); --force overrides.
  Panel schedule-time route already had this guard; CLI is now covered.
- reuters-technology record rebuilt from its valid attempt1 envelope
  (SUCCESS, 10 articles, matching push syncstate).