How can I best prepare myself to keep the option for academia open, after leaving for industry?
In Germany there are actually quite a lot of such positions at the so-called Fachhochschulen. To be a professor there, it is actually expected to have worked in Industry for at least 3 years (or so, depending on the state) and share your industry experience for a more applied education of students. Of course, an excellent PhD is also necessary. And usually one needs to have some form of achievements while being in industry; e.g. papers, presentations, patents, rise to leadership positions, cooperations with academia, or similar; such that continued applied reseach can be expected.
This is in addition to the comments of @user2768 and @A rural reader.