fn link_segments_cjk(outline: &Outline, axis: &mut Axis, scale: i32)
Link segments to form stems and serifs for the CJK script group.
See https://gitlab.freedesktop.org/freetype/freetype/-/blob/57617782464411201ce7bbc93b086c1b4d7d84a5/src/autofit/afcjk.c#L848