v0.5.0: round-1 revision feature release for G3 (MS G3-2026-406681)

bump version to 0.4.0

bump version to 0.3.0

bump version to 0.2.0

bump version to 0.1.2 and add PyPI publish workflow

Add trusted publishing workflow via GitHub Actions for automated
PyPI releases on version tags.

feat: add Direction of Selection (DoS) statistic

Add the DoS statistic from Stoletzki & Eyre-Walker (2011) to MK test
results. DoS provides a symmetric, bounded measure of selection that
complements alpha and NI.

Formula: DoS = Dn/(Dn+Ds) - Pn/(Pn+Ps)
- DoS = 0: Neutral evolution
- DoS > 0: Positive selection
- DoS < 0: Slightly deleterious polymorphisms

Included in all output formats (pretty, TSV, JSON) for both standard
and polarized MK tests.

Release v0.1.0 - First release