Always start xochitl if tarnish determines it can't start oxide or decay

[danshick]

Is your feature request related to a problem? Please describe.
If oxide or decay fails to run for any reason (especially after a system upgrade), a user could be unable to access any graphical application on the device and may not know a new ssh password reset by the update.

Describe the solution you'd like
If tarnish fails to start an app that can put something on the screen, it should load xochitl as a failsafe.

Describe alternatives you've considered
Maybe instead of loading xochitl, it could disable itself and reenable xochitl? Or even wait for some type of signal (network, button based, etc.) to perform this failsafe procedure.

[Eeems]

If tarnish fails to start an app that can put something on the screen, it should load xochitl as a failsafe.

This requirement is too strict. If on startup it fails to load either the launcher or the startup application it should switch out to xochitl.

Maybe instead of loading xochitl, it could disable itself and reenable xochitl? Or even wait for some type of signal (network, button based, etc.) to perform this failsafe procedure.

I'd rather not have mess around with what is enabled vs not enabled as part of the tarnish startup code. I'll just do my best to return the user to a state where they can use the device.