- freq>=2 with a preferred window now means: first run in the overnight
  deadline batch + remaining runs spread in the window (reuters-world
  2×/day+morning → 04:00 overnight + 07:00 morning)
- global min gap is a dropdown on the schedule board (10..120 min),
  saved via /schedule-gap and immediately re-planned
- applied: gap 30min, reuters-world 04:00/07:00