Another svg not importing.

[NicTanghe]

svg orig

svg rendered.

[NicTanghe]

OK so 2 Issues,

1. usvg resolves mask="url(#logoMask)" into usvg::Group::mask().
   Graphite reads group.children() and group.clip_path(), but never reads group.mask().

2. SVG output explicitly generates mask-type="alpha", while Vello
   uses alpha-based SrcIn compositing.

perhaps

3. Honor SVG mask regions and coordinate units
   • Preserve Mask::rect().
   • Correctly constrain rendering using x, y, width, height, and resolved maskUnits.
   • Test both userSpaceOnUse and objectBoundingBox.