The first positional CLI argument (default localhost) names the site's
public hostname and its data directory under the cwd, replacing the
CWD-relative pagerite.* files. The public origin (https://<hostname>)
is now authoritative configuration instead of a value learned from
admin browsers: POST /_api/site-url, Data.site_url and the pagerite.js
reporter are removed, and page rendering, sitemap, robots.txt and
analytics own_origin all use SITE_URL consistently (localhost falls
back to the request's base URL).