fix: TopNav 모바일 오버레이 body scroll lock + 푸터 연도 2026 통일

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/components/DashboardShell.tsx

@@ -67,7 +67,7 @@ export default function DashboardShell({ children }: { children: React.ReactNode
                 <a href="/legal/privacy" className="text-slate-400 hover:text-[#1a56db] transition underline underline-offset-2">개인정보처리방침</a>
                 <a href="/legal/refund" className="text-slate-400 hover:text-[#1a56db] transition underline underline-offset-2">환불 정책</a>
               </div>
-              <p className="mt-2 text-slate-400">© 2025 쟁승메이드. All rights reserved.</p>
+              <p className="mt-2 text-slate-400">© 2026 쟁승메이드. All rights reserved.</p>
             </div>
           </footer>
         </main>

app/components/TopNav.tsx

@@ -26,6 +26,14 @@ export default function TopNav() {
 
   useEffect(() => { setOpen(false); }, [pathname]);
 
+  useEffect(() => {
+    if (open) {
+      const prev = document.body.style.overflow;
+      document.body.style.overflow = 'hidden';
+      return () => { document.body.style.overflow = prev; };
+    }
+  }, [open]);
+
   const isActive = (href: string) =>
     href === '/' ? pathname === '/' : pathname.startsWith(href);