{# `data-fcu-auth` / `data-fcu-menu` stamp the shell's session and menu; construct-core.js compares them with the X-Construct-Auth / -Menu response headers (see technical/architecture.org → The Main Menu). #}
{# Varies per page (construct.page_title folds in the active view's name), so navigating between list/create/edit changes the document title. #}