framework : Prepare Maven Central publication (alpha2)

[farah-t-trigui]

As a developer,
I want the project to be compliant with Maven Central requirements,
So that we can publish a stable release (alpha2).

[farah-t-trigui]

• Complete required metadata in pom.xml (name, description, url, licenses, developers, scm)
• Configure source JAR generation (maven-source-plugin)
• Configure Javadoc JAR generation (maven-javadoc-plugin)
• Set up GPG signing (maven-gpg-plugin) and generate .asc files
• Configure Sonatype (OSSRH) publication (distributionManagement)
• Manage credentials (GPG + Sonatype) via CI/CD secrets
• Ensure release version is not -SNAPSHOT
• Define and apply Git tagging strategy for release