[MCOMPILER-374] - Unable to compile MR-JAR code against older directories when module-info.java is present

[wilx]

Summary

• Include existing output directories for earlier MR-JAR releases in the --patch-module path when the current compilation contains module-info.java.
• Reuse the same ordered output-directory list for the compiler class path and module patch path.
• Add an integration test covering release 8 base classes, a release 9 layer, and a modular release 11 layer that references a release 9 class.

Motivation

The plugin already added earlier MR-JAR output directories to the class path. Once module-info.java is present, however, javac resolves the sources as a named module and the class path alone does not make those earlier classes part of that module.

The existing --patch-module option only contained the base output directory. The patch path now contains each existing earlier release directory in descending order, followed by the base output directory. This matches MR-JAR shadowing order and lets the modular execution see the output of earlier executions.

Fixes #579

Testing

• JAVA_HOME=/opt/jdks/latest-17 /opt/maven/latest/bin/mvn clean verify
• JAVA_HOME=/opt/jdks/latest-17 /opt/maven/latest/bin/mvn -Prun-its clean verify
• JAVA_HOME=/opt/jdks/latest-17 /opt/maven/latest/bin/mvn -Prun-its -Dinvoker.test=MCOMPILER-374_mrjar clean verify
• JAVA_HOME=/opt/jdks/latest-17 /opt/maven/latest/bin/mvn -Prun-its -Dinvoker.test=MCOMPILER-373_mrjar clean verify

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