Use uv for various things around CI

[alex]

• uv build for building cryptography sdists + vectors sdists/wheels
  • Accept --build-constraints in uv build astral-sh/uv#7085
  • Add --require-hashes and --verify-hashes to uv build astral-sh/uv#7094
• uv build for building cryptography wheels
  • Linux
    • [Bot] Update dependencies pypa/manylinux#1670
  • macOS
  • Windows
• uv pip compile for managing .github/requirements/build-requirements.txt
  • Locking of build dependencies astral-sh/uv#5190
• uv pip compile for managing .github/requirements/publish-requirements.txt
• uv pip compile for managing ci-constraints-requirements.txt
  • uv pip compile --universal fails when dependency's python-requires is incompatible with -p, even with markers astral-sh/uv#6730
• Pin uv in wheel-builder.yml

[alex]

@charliermarsh if you were curious how all the pieces I've been requesting fit together, this is it.