Improvements and fixes to Deco GUI and Factions system - #685

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-java@v4, gradle/actions/setup-gradle@v3.5.0, phoenix-actions/test-reporting@v15. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

This job uses deprecated functionality from the 'gradle/gradle-build-action' action. Consult the Job Summary for more details.