Write or install a bx-sites (ortus-boxlang/bx-sites) plugin - the models/BxSitesPlugin.bx build-lifecycle hooks (onConfig, onPageMarkdown, onPageHtml, onNav, onSearchIndex, onSitemap, onBuildComplete), installing a published plugin from ForgeBox, and registering new bxSites CLI verbs via models/BxSitesCliProvider.bx. Use this whenever a user wants to extend bx-sites' build pipeline with custom logic, or add a new bxSites <verb> command.
