Was macht nextjs-cache-architecture?
Use this skill whenever the user wants to design or implement caching in a Next.js 16+ App Router project — setting up the "use cache" directive, building a cache tag registry, wiring mutations to invalidation utilities, structuring Suspense boundaries for partial prerendering, handling personalized content near cache boundaries, choosing cacheLife profiles, calling cacheTag / updateTag / revalidateTag correctly, migrating from unstable_cache, or debugging stale or incorrectly fresh data. Trigger even when the user only describes their domain (e.g. "I have a posts table") and asks how to cache it properly.