- @hm-design/chart: add --hm-chart-track (radial tracks, horizontal bar
hover band; warm neutral light) and --hm-chart-surface (slice / segment
gaps, Dot rings, label halos, radial meter center; white by default)
- --hm-chart-bar-name-halo stays an optional override and falls back to
--hm-chart-surface; official chart.tsx unchanged
- Storybook Chart pages (Bar / Line / Area / Donut / Pie / Radar / Radial):
open layout without example cards, 2-4 responsive columns, one sample
data notice per page, surface token set to the content background
- Same sample data, props, tooltip and interaction as the example cards;
examples entry and consumer example unchanged
- README: surface / track token usage
