I made some mistakes when I was setting up HTTrack, and now my website backup
has a big chunk of Wikipedia in it, among other sites. A lot of sites. HTTrack
purged some unnecessary files once I got my settings correct, but many still
remain (I assume because I canceled the operation so many times while trying
to figure out what was going on!)

Is there any way I can tell HTTrack to scan through the local directory
structure and delete files/folders that aren't part of the cache or backup?