For powsybl-hpc/computation-mpi/src/main/java/com/powsybl/computation/mpi/generated/Messages this is a generated file so maybe we should configure the scanner to exclude it. It does not make sense (or maybe is illegal?) to add a licence/authorship to a generated file.
For the preventive strategy, I would go for a Maven plugin instead because we can test it locally before pushing the code (same kind of check as checkstyle). Indeed it will only check Java files but that is 99% of our files (powsybl cpp excluded)