The shared stroke geometry now has its own arc-length dash generator: a dash
of length 0 becomes a dot that a round cap paints as a disc and a projecting
cap as a square turned along the path (a butt cap paints nothing). Dashes
restart per subpath, join across the start of closed subpaths, and a pattern
too fine for the path draws solid. The canvas and raster export use it through
line_outline; the stroke.set params doc says how to get dots.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>