Seems like it works. I'm questioning if build-helper-maven-plugin is really needed here, since maven is capable of concatenation of property values by itself:

    <properties>
        <dist.archive.base.file.name>keycloak</dist.archive.base.file.name>
        <dist.archive.base.dir.name>${dist.archive.base.file.name}</dist.archive.base.dir.name>
        <dist.archive.dir>${dist.archive.base.dir.name}-${project.version}</dist.archive.dir>
    </properties>

but it seems you want to trim any suffixes on the version number:

keycloak-999.0.0-SNAPSHOT/
vs
keycloak-999.0.0/

Perhaps a more generic thing to do here would be to use build-helper-maven-plugin to generate a project.version.suffixless or something, and then use that to let maven itself concat that with whatever we need, which is dist.archive.base.dir.name in this context. This would align with project.version.npm which was added recently for a different purpose.