BUILD-9398 Create config-gradle action

[GabrielFleischer]

BUILD-9398

This PR proposes a starting point for the config-gradle action.

Here are two successful runs using the updated build-gradle and config-gradle.

https://github.com/SonarSource/sonar-scala/actions/runs/18741627470/job/53478541959
https://github.com/SonarSource/sonar-jacoco/actions/runs/18747526746/job/53478552769?pr=134

Still left :

• Update README
• Add tests

[sonarqubecloud]

SonarQube reviewer guide

Summary: Adds config-gradle action with build environment setup and includes coverage tracking

Review Focus: New config-gradle action implementation including version management, authentication setup, and caching. Updates to build-gradle to use the new config action. Documentation restructuring with clearer action relationships.

Start review at: config-gradle/action.yml. This is the core new functionality that centralizes Gradle environment configuration and will be used by build-gradle, making it critical to validate the action definition, inputs/outputs, and integration points.

💬 Please send your feedback

Quality Gate passed

Issues
0 New issues
0 Accepted issues
0 Dependency risks

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[matemoln]

Thanks @GabrielFleischer for the contribution!