Refactor admin area and remove legacy root paths

components/layout/app-sidebar.tsx

@@ -66,7 +66,7 @@ export function AppSidebar({
       <AppCard className="overflow-hidden bg-sidebar text-sidebar-foreground shadow-sidebar">
         <CardHeader className="pb-4">
           <p className="text-xs font-semibold uppercase tracking-[0.24em] text-sidebar-foreground/56">
-            Root Access
+            Admin Access
           </p>
           <CardTitle className="text-base font-semibold">{title}</CardTitle>
           <p className="text-sm leading-6 text-sidebar-foreground/72">{description}</p>

components/layout/site-footer.tsx

@@ -36,7 +36,7 @@ export function SiteFooter({ isAdmin = false }: SiteFooterProps) {
           ))}
           {isAdmin ? (
             <a href={buildAdminUrl()} className="text-muted-foreground hover:text-foreground">
-              {tNav("root")}
+              {tNav("admin")}
             </a>
           ) : null}
         </nav>

components/layout/site-header.tsx

@@ -315,7 +315,7 @@ export function SiteHeader({
               />
               {isAdmin ? (
                 <Button asChild variant="ghost" size="icon" className={desktopControlButtonClassName}>
-                  <Link href={buildAdminUrl()} aria-label={t("root")}>
+                  <Link href={buildAdminUrl()} aria-label={t("admin")}>
                     <LayoutDashboard className="h-4 w-4 transition-transform duration-300 ease-out hover:scale-110" />
                   </Link>
                 </Button>
@@ -465,7 +465,7 @@ export function SiteHeader({
                       />
                       {isAdmin ? (
                         <Button asChild variant="ghost" size="icon" className={mobileControlButtonClassName}>
-                          <Link href={buildAdminUrl()} aria-label={t("root")} onClick={() => setIsOpen(false)}>
+                          <Link href={buildAdminUrl()} aria-label={t("admin")} onClick={() => setIsOpen(false)}>
                             <LayoutDashboard className="h-4 w-4 transition-transform duration-300 ease-out hover:scale-110" />
                           </Link>
                         </Button>