Impact Analysis uses https://github.com/puppetlabs/PipelinesInfra/blob/main/src/main/java/com/puppet/pipelines/cdpe/PECatalogDiffer.java to determine differences between two catalogs. As this is the logic we are most interested in from cd4pe, we should extract it in a different Java program.
The initial implementation should only be able to read two catalogs from disk, determine the differences and write them to disk.