- Use BUILD_REPO/DIST_REPO split so zip contains only runtime deps
(build-lifecycle plugins, test jars, etc. stay in throwaway BUILD_REPO)
- Minimal inline stub pom.xml (no deps) instead of archetype:generate
to avoid polluting DIST_REPO with stub project's own dependencies
- Replace grep -oP (PCRE, unavailable on macOS BSD grep) with Python re
- Use version-aware Python version_key() for max POM version selection
(lexicographic sort fails for e.g. 2.18.10 vs 2.18.6; release > snapshot)
- Write zip to caller's working directory; keep cleanup trap active;
remove `trap - EXIT` which was leaving WORK_DIR behind
