When working with PDF builds, one of the big issues has been that I get into Unicode error issues, and so the scripts in this particular push help find all the non-ASCII Unicodes so that I can fix them manually. Also, another issue that shows up is with figure reference labels, which can be broken. And so, the fig_references script detects those and raises errors.
We put all the QMD files under their own directory structure. The directory contains the QMD file and also an images directory, so each chapter is now self-contained
As part of this reorg, I updated the links to images etc. to make sure they are all pointing to the right location
