When a car is able to get range from Connected Account but not OBD-II, consider updating range based on trip miles driven

E.g. a car with a Connected Account will typically only update range at the start and end of a drive. Sidecar knows the miles you're driving while navigating, so it could in theory simulate the range reduction in this case so that the range widget is more accurate.

The issue names no files, tests, or entry points. First locate the range widget and the navigation/trip-mile data path, then clarify how Connected Account and OBD-II ranges should interact. Done means the agreed behavior is implemented and the widget reflects trip miles without conflicting with the next account update.

Written by the indexing model from the issue text.