Re-bucket the channels at high resolution within a distance window — the
chart's payoff when a split/lap is locked and zoomed: the same lines, but
resolved to ~10 m instead of the whole-activity 100 m grid, revealing detail
the overview averages away. Distances are absolute, so the result drops into
the same axis as ActivitySummary.channels and the chart's range clip.
Re-bucket the channels at high resolution within a distance window — the chart's payoff when a split/lap is locked and zoomed: the same lines, but resolved to ~10 m instead of the whole-activity 100 m grid, revealing detail the overview averages away. Distances are absolute, so the result drops into the same axis as ActivitySummary.channels and the chart's range clip.