We stay on Contentful for content. How do I actually wire Croct into our Next.js app?

Keeping content in Contentful, no plan to re-platform the CMS. We dropped our old add-on and now want personalization and A/B testing on the Next.js frontend.

I already load Contentful data in my server components. What I need is the concrete wiring: how does a Croct slot get fetched alongside that, and what goes where. Not looking for the marketing overview, just the setup