[mveril]

Summary

• Upgrade the locked PySCF dependency to 2.15.0 and enable its native Windows x86-64 wheel.
• Run the reference suite on supported Linux, macOS, and Windows runners, and preserve the provenance of the PySCF 2.14 integral fixtures while comparing them numerically with 2.15.
• Preserve Cargo diagnostics when an integral export is incomplete and update platform and scientific documentation.

Validation

• uv run --locked pytest tools/reference tools/test_book_links.py: 95 passed on Windows x86-64, Python 3.14.
• uv run --locked pytest tools/reference/test_integrals.py -q: 3 passed.
• uv lock --check; Ruff checks; mdBook build and test; documentation link checks; git diff --check.
• The 30 stored integral arrays differ from PySCF 2.15 by at most 4.45e-16 in absolute value. The existing 1e-13 fixture comparison tolerance is unchanged.
• The new native CI matrix covers Linux x86-64 and ARM64, macOS Intel and Apple Silicon, and Windows x86-64; Windows ARM64 has no native PySCF wheel.