after strokes => filled paths, small curves look incorrect

look at the monocle's chain links in the attached GIF: they should be perfectly circular but after picosvg they look wrong


I suspect this has to do with the way we convert conic curves to quadratic in skia-pathops (following the stroking operation).

Start by reproducing the monocle chain-link distortion shown in the attached GIF after picosvg processing. Inspect the skia-pathops conic-to-quadratic conversion that follows the stroking operation, and compare the resulting small curves with the expected circular links. Done means the links remain circular after stroke expansion and path conversion.

Written by the indexing model from the issue text.