feat(settings): add opt-in atomic write mode - #29

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, actions/setup-dotnet@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Possible null reference argument for parameter 'path' in 'void File.Delete(string path)'.

Dereference of a possibly null reference.

Possible null reference argument for parameter 'path' in 'void File.Delete(string path)'.

Dereference of a possibly null reference.