Versioning & publishing

Taking a site from a local build to a published, versioned one: the mode chosen at scaffold time, cutting a release, and the workflows that actually publish it.

Versioning modes — Standalone (Stable + Prerelease) vs. Versioned (Full History), decided once at scaffold time.
Branching model — trunk-based vs. git-flow, switchable later with docouture branch-model.
Releasing a documentation — cutting a release via docouture-release.yml, manually or on a labelled merge to main.
Publishing a documentation — the prerelease and release publish workflows that run docouture publish gh-pages.