It’s a great question, because like many things here, there is a supported way that is a bit cumbersome and a way through a user script that works very well for users like me.
Built into WK is a way that only allows item-by-item resurrection (as someone already stated)… I recommend bookmarking the following script for later use:
[Userscript] Burn Manager (Review / Resurrect / Retire)
This script can probably eliminate the need for level reset for most users. I like this because it allows me to reset old items level-by-level, while keeping the upper level un-burned items in the mix as well.