Each stage-transition activity now becomes a horizontal range on its lane: start = the activity's date, end = the next activity with a higher stage rank, or extending to today if still in effect. Milestone date-field dots overlay on top of the ranges. Activity dots at each range start carry a tooltip with the activity subject. Added computeStageRanges in lib/stageRank.ts and switched DateTimeline to take activities directly (deriving both the rank resolver and the ranges internally). Wide year-spanning timelines now show their full extent even when no milestone dates have been entered.