rust-index: slicechunktodensity returns Rust result Ready for removal of the scaffolding. This time, we allow ourselves a minor optimization: we avoid allocating for each chunk. Instead, we reuse the same vector, and perform at most one allocation per chunk. The `PyList` constructor will copy the buffer anyway.

[build-system]
requires = ["setuptools", "wheel"]

[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
'''
skip-string-normalization = true
quiet = true