Now that Python 3.13.0b1 is out, time to get at least a 6.0.2 pre-release out the door with 3.13 support. Most everything is working, but there are a couple of deferred housekeeping things that I'm still finishing up...

• Support for Cython 3.0+ (via conditional old_build_ext import)
• Custom cibuildwheel with 3.13 support
• Update CI.yaml to use dynamic matrix (eliminate extra copy for release)
• Support for macos-14 GHA runner (native Apple Silicon, reduces need for our self-hosted runners)
• Update libyaml Mac shared build to work with newer autoconf
• Support for windows-2022 GHA runner
• Update libyaml Windows shared build to run under VS2022