Should textbook acknowledgments be included as publications on a CV?

You can put anything on your CV that you think contributes to your professional standing. For honesty, I'd suggest using a separate section, however, not the "publications" section unless you are listed as an author. Perhaps something like "Contributions to published work" or similar.

Overstating the case can have a negative impact, not the positive one you want.

The universal convention in academia, and I’m guessing anywhere else, is that listing something in your CV under “Publication” implies that you’re an author or coauthor of the work.

So if you’re not a named author but only listed in the acknowledgements section, you should not list the work in the Publications section. It would be seen as dishonest or at least misleading and reflect poorly on you, even if you added some asterisk or footnote to indicate your role.