[ns-ui] A travel-time reach editor: one slider handle sets minutes, and the reach renders as topographic-style contour bands re-thresholded from a real per-node cost field via marching squares, with every third line heavier and labelled inline in a break in its own stroke.
pnpm dlx shadcn@latest add "https://registry.directory/r/nikolas-sapa/index-contour.json"