* [wip] upgrade rollback test

* rollback tests passing
(wip) update from stable almost passing

* update lib with suggestion

* all around fixes

* ensure charm is a Path object

* pr comments and workflow fix

* bump operator_cache

* update lock

* fixes

* not needed

* constrained deployment

* addressing comments and test fix

* several fixes for upgrade from stable

* cos lib bump

* invalid arg

* ditch root usage

* fix perms for backup

* typing improvs

* noop if not running

* bigger ci timeout

* revert permission fix

* to fix on another PR

* split upgrade from stable

* revert test change

* don't set group as it will break backups