Feat
- add gvl.update for atomic post-hoc track addition
- parallelize gvl.write over track categories (variants first)
- gvl.write accepts annot_tracks
- polars-bio annotation extraction + bigwig annot source
Fix
- guard duplicate track names in update; flat_ends symmetry; test polish
- restore DATASET_FORMAT_VERSION attribute docstring placement
- pyrefly search-path resolves local source; drop stale ignore and unused import
Refactor
- remove Dataset.write_annot_tracks and _annot_to_intervals
- _write_track takes explicit out_dir; add _write_ragged_intervals