v0.9.0

What's New

3D Polygon Operations

• Add 3D polygon boolean and offset wrappers, including plane-offset support
• Add 3D analytical and transform polygon wrappers with full API documentation
• Add simplify_polyline for 3D polylines

2D/3D Separation & Architecture

• Implement 2D/3D separation with planar-only docs, Z-fix in offset, projection helpers, 2D clipping split, planar namespace, and tests
• Upgrade Command::Arc from 2D to 3D (center_offset: Point3D, normal: Point3D)

Breaking Change

• Replace custom Point/Point3D structs with glam::DVec2/glam::DVec3 type aliases

Improvements

• Promote spatial_grid → spatial_grid2d from nest2d to geo::algo
• Deduplicate nfp_convex_fast by routing to minkowski2d::get_no_fit_polygon

Bug Fixes

• Fix perpendicular_3d handedness and endpoint offset direction

Documentation

• Improve API doc generation with multi-line param/returns descriptions, PEP8 signature wrapping, shorter type names, and Python code blocks
• Return value descriptions are now in tables, fix notation markup
• Add API doc visualizations for polygon3d functions