v0.6.7: really include Python 3.14 wheels

I forgot to update cibuildwheels in my PR preparing 0.6.6, so it didn't include Python 3.14 wheels.

This release just rolls in the required CI fixes and other CI improvements.

What's Changed

• fix build_wheels so we actually get the Python 3.14 wheels, and other fixes by @joanise in #77

Full Changelog: v0.6.6...v0.6.7