0.20.2

Changed

• SinglePointData.normal_modes_cartesian is defined precisely: each mode is a Cartesian displacement (not mass-weighted) scaled to unit length, dimensionless, in the input structure's frame and atom order, ordered like freqs_wavenumber, with arbitrary sign. The previous description ("displacements in Bohr") left the scale undefined, and programs disagreed.
• The documentation site is built and published by a Docs workflow on every release tag (or by hand), instead of locally. Pinned pymdown-extensions below 11, which broke the docs build.