- Emit transformed analytical curves (circles, arcs, ellipses) in block
expansion as standalone wires rather than merging them into batched line
strips.
- Keep render_instance unset on analytical curves in block prototypes so
they route directly to CircleGpu / EllipseGpu instead of BlockWireGpu.
- Support TangentGeom::Circle in extract_circle_instance and wire partitioning.
- Drop analytical tangents on wires clipped by xclip so clipped geometry
falls back correctly to line segments.
- Add unit test verifying block circles and arcs extract as analytical GPU
instances.