slugify() produces ASCII-only lowercase slugs from arbitrary text (used for
artist slugs and tag slugs). paths.derive_subdir/derive_top_level_artist
extract the destination layout and folder→artist convention from an import
source path. hash_suffixed_name builds IR-style 'stem__hash10.ext' filenames.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
bvandeusen