- New update.sh: detects Alpine, Arch, Debian/Ubuntu, RHEL/Fedora/CentOS,
openSUSE, Void, Gentoo and updates the package index only (no upgrades)
- clean.sh fixes:
- Fix ((cleaned_count++)) exiting under set -e on first successful rm
- Stop recursively deleting /var/cache and /root/.cache wholesale
- Add CACHE_RETENTION_DAYS (7d) — clean_directory now only deletes
files older than retention period instead of wiping everything
- Remove dangerous rm -rf fallback in clean_directory
- Narrow CACHE_DIRS to /var/cache/apt instead of /var/cache
- Fix /home/*/.cache pattern to only target pip/npm caches
