abdenlab/oxbow: v0.6.0

New Features Zero-column projection support — record batch builders now accept zero-column projections and preserve row counts when no columns are projected. (#160) Multithreaded BGZF reader support — Widened trait bounds allow callers to pass bgzf::io::MultithreadedReader to scan methods. (#164) Backtrace capture in errors — Six crate-level error variants (InvalidInput, InvalidData, NotFound, Io, Arrow, External) with backtrace captured at creation time (displayed when RUST_BACKTRACE=1). On the Python side, variants map to PyValueError, PyKeyError, or PyIOError. (#166) API changes Schema definition separate from projection: scanner schemas are now declared at construction time and scan methods project onto the declared schema. (#161) Schema-defining parameters (fields, tag_defs, attr_defs, info_fields, genotype_fields, samples, etc.) move from scan() arguments to Scanner::new(). Scanners validate and cache their Arrow schema at construction. Scan methods now accept only columns (projection), batch_size, and limit. Discovery methods like tag_defs() and attribute_defs() are now static/standalone rather than instance methods. New traits: shared RecordBatchBuilder and Push<T> traits for record batch builders (#160) schema() now returns the cached schema (not computed on the fly). Widened BGZF trait bounds on scan methods (#164) scan_query, scan_unmapped, and scan_virtual_ranges accept generic R: bgzf::io::BufRead + bgzf::io::Seek instead of concrete bgzf::io::Reader<R> Custom crate error type: OxbowError replaces io::Error (#166) All public scanner methods and the Push<T> trait now return crate::Result<T> (alias for Result<T, OxbowError>). TryFrom/FromStr impls use type Error = OxbowError. Maintenance Module paths renamed: <family>/format/ directories renamed to <family>/scanner/, with batch_iterator nested underneath. All public re-exports preserved at the family level, but direct path imports will break. (#163) Unified BED schema model: Shared BedSchema, FieldDef, and FieldType type system (37 AutoSql variants) extracted into bed/model/field_def.rs, used by both BED and BBI formats. (#161) Export version variable for inspection in py-oxbow. (#162) Dependency Upgrades: noodles 0.107, Arrow 58, PyO3 0.28, pyo3-arrow 0.17, Rust toolchain 1.94. (#165) Full Changelog: https://github.com/abdenlab/oxbow/compare/v0.5.2...v0.6.0