Fix: NavDropdown link navigation with stopPropagation

Prevent click-outside event handler from interfering with link navigation
by adding stopPropagation to both section and flat link click handlers.

Fixes issue where clicking a dropdown link from a product page would not navigate.

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

src/components/NavDropdown.tsx

@@ -53,7 +53,10 @@ export default function NavDropdown({
                         <Link
                           key={link.href + link.label}
                           href={link.href}
-                          onClick={() => setOpen(false)}
+                          onClick={(e) => {
+                            e.stopPropagation();
+                            setOpen(false);
+                          }}
                           className="block px-4 py-2.5 text-sm hover:bg-surface"
                         >
                           {link.label}
@@ -68,7 +71,10 @@ export default function NavDropdown({
               <Link
                 key={link.href + link.label}
                 href={link.href}
-                onClick={() => setOpen(false)}
+                onClick={(e) => {
+                  e.stopPropagation();
+                  setOpen(false);
+                }}
                 className="block px-4 py-3 text-sm hover:bg-surface"
               >
                 {link.label}