Document building a preview entrypoint #12943
Description
📚 Subject area/topic
Adapter API
📋 Page(s) affected (or suggested, for new content)
https://docs.astro.build/en/reference/adapter-reference/#previewentrypoint
📋 Description of content that is out-of-date or incorrect
We do not document at all how to make an adapter support astro preview. We should probably have a section "Building a preview entrypoint" just like we have "Building a server entrypoint".
🖥️ Reproduction in StackBlitz (if reporting incorrect content or code samples)
No response