Prepare the 0.3.0 release for the merged cross-platform support train.\n\nScope:\n- finalize CHANGELOG.md and VERSION\n- validate the package artifacts\n- create the matching v0.3.0 tag\n- rehearse publication on TestPyPI and publish to PyPI after approval\n\nThe release should include the changes currently listed under Unreleased.
Prepare the 0.3.0 release for the merged cross-platform support train.\n\nScope:\n- finalize CHANGELOG.md and VERSION\n- validate the package artifacts\n- create the matching v0.3.0 tag\n- rehearse publication on TestPyPI and publish to PyPI after approval\n\nThe release should include the changes currently listed under Unreleased.