Provide a direct link to the PDF.
This is a good idea so that the book can be linked and opened directly as opposed to having the user download a zip file and extract it.
Where would the PDF be hosted? Or do you suggest to check in the PDF file to the git repository (which means large commits each time)?
I was thinking hosting on github. It does not seem like the book changes all that much these days. It can be a separate repo too. Check out how Bartosz does it https://github.com/BartoszMilewski/DaoFP.
Big fan of your work btw. Your linear algebra book is 🔥 .
Also I'm not sure if this will be large as only the pdf diff is committed right?
I think PDF diffs are large because the entire file is changed.
Git does binary diffs for pdfs. Look into it.