I don’t think that I see us adding ipdb as a dependency. One of the tenets of the OF is to be as close to zero dependencies outside of the Python standard lib as possible. Ipdb is wonderful, but pdb is fit for purpose, and comes built in.
Feel free to import and invoke it in your charm, though. I’d even say that monkey patching ops.framework.pdb isn’t the worst idea. You’d be able to piggy back on the code that drops you into a debugger as soon as a hook executes, without too much risk that you’ll break something relevant for production.