- Add install/snappymail/plugins/list-unsubscribe-header (upstream GitHub plugin)
- Add plogical/snappymail_plugin_utilities.py to copy into snappymail + legacy rainloop data roots and merge enabled_list
- Run after SnappyMail CyberPanel installer in install.py and upgrade.py
- InstallMailBoxFoldersPlugin now merges plugins instead of replacing enabled_list; also installs list-unsubscribe
Roundcube is not shipped by CyberPanel core; SnappyMail is the bundled webmail.
