feat(zig): add bindings/zig, example/zig-hello and Linux/macOS CI on Zig 0.17.0 - #321

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/