Save Windows vcpkg cache before tests

[adsharma]

Summary

• split the Windows vcpkg cache step into explicit restore and save actions
• save the populated vcpkg binary cache immediately after the Windows dependency install succeeds
• keep build and test failures from discarding the expensive vcpkg binary cache upload

Root cause

The combined actions/cache step only saves during post-job cleanup after a successful job. If Windows tests fail after vcpkg spends ~40 minutes building Arrow, the new C:\vcpkg-binary-cache contents are not uploaded, so the next main run is cold again.

Validation

• git diff --check
• parsed .github/workflows/build-and-deploy.yml with Ruby YAML.load_file