Committed another change that sets the tracker’s state to driving only if the entity is not in a HA Zone. Also, made it translatable. The state itself will now be all lowercase driving, whereas the “en” translation is “title case”, i.e., “Driving”. So, in the UI it will look like before (Driving), but any automations would need to check for lowercase (driving).
I still have quite a few "TODO"s commented in the code, so there will still be quite a few changes before I’m ready to release a beta (installable via HACS.) Other than tracker entity state restoration (which I plan to do next), most of the basics should now be in place. The rest is somewhat “fluff” (like testing. 
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