v0.1.1

v0.1.1: cross-section examples, isobands improvements, build fixes

cross-section examples
- new live example with WASM, VTK C++, and Python VTK implementations
- extracts isocontours and triangulates into filled polygons
- interactive plane movement with scroll

isobands improvements
- make_isobands with return_curves now only returns curves for selected
  bands instead of all intersection edges
- fixed lifetime bug in segments reindexed() where block_indirect_range
  held iterators to temporaries from a lazy mapped_range
- examples updated to match cross-section style: single viewport,
  semi-transparent mesh, teal colors, fixed plane through centroid

triangulation
- ear cutter auto-detects and corrects clockwise polygons
- added 2D and clockwise polygon tests

build
- sdist now included in PyPI publish workflow
- ninja required for sdist builds