convenient bolt + adapter for a thin table for "Flexible & sturdy phone arm"

the model is a remix and includes several improvements to the original project by @FunkyArt_274361
https://www.printables.com/model/647794-flexible-sturdy-phone-arm-100-printed

added an adapter for thin tables since the original model does not secure well on them or does not secure at all.
added a convenient bolt that is easier to screw in.