Rework Settings system - #64

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

AdoptOpenJDK has moved to Eclipse Temurin https://github.com/actions/setup-java#supported-distributions please consider changing to the 'temurin' distribution type in your setup-java configuration.