Constant SITE_ROOT 

pub const SITE_ROOT: &str = "https://andrejorsula.github.io/atune/";

The published site’s root, one segment above SITE_PAGE_PREFIX.

What detection keys on. A version segment is data, so a scan that hard-codes one can only ever see the citations that are already right — which is the difference between a check and a coincidence. site_version_segment splits a match into its segment and the page path after it.