We’ve installed the vanity lights! The wiggly wires are gone:

The electrician was quick- installed three fixtures and a switch in about an hour:

Left to right: with bulb, without bulb, without cover:

And “after”:

The bulbs are currently 150 watt incandescent T10s (they’ll be on a dimmer) and apparently they’re also partially malfunctioning… Shipped that way, damaged in transit or damaged in the 1.25 years since we’ve been storing them who knows. So we ordered some more (in 60 watt instead) and they’re on their way!