OpenAPI Overlays for Splitting Public and Internal Documentation

Continuing my walk through the many use cases for OpenAPI overlays, I want to sit with one that hits close to how most teams actually ship docs. You have a single OpenAPI definition, but you need it to produce two documentation sites: a clean, branded public developer portal, and a richer internal portal that your own engineers and support folks live in. The internal one carries admin endpoints, debugging notes, and links to your ops runbooks.