set ship mode on shutdown via GUI
phosh could, in a failsave way (check whether the right charge controller is available via i2c / so that phosh can run on any other device as well), set shipmode when powering down via the GUI.
Since this is probably the most common way how to shutdown, it would prevent the battery from draining in a lot of cases.
see also https://source.puri.sm/Librem5/linux-next/-/issues/120