My 2015 Pure has manual headlight controls- with its black plastic housing tip popping off constantly which gave me an idea- perhaps the manual headlight switch can be swapped for another switch with an integrated module containing a light sensor behind a translucent plastic that could automatically control the operation of the headlights based on ambient lighting. Anyone know if there is a part I can readily purchase?

If not, maybe the existing switch can be modded so that the "ON" position is used with a light sensor so that when lux dips below a specified value it will complete the circuit and turn the headlights on so that the switch can be left in the "ON" position all the time.

The only issue is that the headlights operate independently of the ignition state which would kill your battery. OTOH, the car knows when you left the lamps on and beeps if you open the door with the ignition off, so there is probably circuitry that can be tapped into.