Publish Markdown safely for search and sharing

A specific title and description help readers decide whether the page answers their question. Author, tags, language, cover, and canonical URL must describe the reviewed revision rather than newer private content. Indexability is an API-controlled state, not a client-side checkbox alone.

Changing a handle or slug should reserve the new route atomically and retain a permanent redirect from the old route. A redirect prevents broken inbound links while moderation and visibility still decide whether the target is public.

Owner-only private shares, unlisted token shares, optional password/expiry, and copy/source/PDF permissions are distinct controls. An unlisted URL should remain noindex; a public publication still needs moderation, rate limits, abuse reporting, and operator response.

The repository provides fail-closed moderation state, route/report rate limits, audit evidence, and runbooks. Production still needs approved policy ownership, external malware/spam engines, edge limiting, CDN purge integration, on-call handling, and a real legal/domain review.