I did this recently too, didn't really care about the code quality of a small tool, just asked Claude to add in the features I wanted and it produced something that worked.

I just pushed the changes to my fork of the project and left it at that. Leaves the feature around for me and anyone that stumbles across my fork, without wasting the original dev's time looking at code I didn't care to look at.

Even before AI coding I think it was relatively common to fork some code and edit it to have something you want, then to either leave it as a personal version, or to never actually get a response on the PR.