I'm pretty certain that there is no such word as 'jewelsmith.'
A smith, specifically, works with metal, a jeweller works with jewels, precious stones. So, a goldsmith would make the setting and a jeweller would polish and cut the stone and set it. Of course, a smith can also be a jeweller, but they are two different trades.
I can't find jewelsmith in Oxford, nor can I find jewel-smith, and, because of the nature of the trades, any combination of jewel smith would be incorrect anyway.
If you are referring to someone who makes jewellery, use the term we already have, a jeweller.