@date/@datetime gain :lang (German: "16. Juni 1910") over a document-wide
Language state variable, and :number for the numeric form (en 6/16/1910,
de 16.06.1910 per DIN 5008). @eval finds Python modules next to the file
that names them regardless of the cwd, and the new :cwd option runs an
eval in a chosen working directory (@source_file uses it to resolve
against the document). Two new test suites ship in tst/.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
