Use when refactoring or extending the shared app shell, route tree, sidebar navigation, or page header for this admin frontend. Read ../../02-information-architecture.md and ../../rules/frontend-rules.md first, keep one shared shell, and stay compatible with Next.js App Router plus Tailwind v3.
Use this skill for shared frontend structure work, not for isolated page content.
../../02-information-architecture.md../../05-design-system-and-rules.md../../rules/frontend-rules.mdapp/layout.tsxapp/page.tsxapp/dashboard/page.tsxcomponents/app-sidebar.tsxcomponents/site-header.tsxcomponents/ui/sidebar.tsx