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Root-project prerequisite for all com.stano plugins. Registers the 'root' BaseExtension exposing cross-project configuration: javaVersion (default '21'), contextName, mspVersion, Docker registry coordinates, Pact Broker coordinates, and lazy CI metadata providers (branch name, commit hash, commit timestamp, build number). Registers the jacocoRootReport task that aggregates JaCoCo coverage across all subprojects. Must be applied to the root project before any other com.stano plugin.

• #convention
• #jacoco
• #java