fix: mobile/responsive issues in FAQ and info pages

- FAQ builder: touch targets 36px → 44px (move up/down/delete buttons)
- Filter tabs: add flex-wrap to prevent overflow on narrow screens
- Accordion: add ResizeObserver for dynamic content height (images
  loading, viewport rotation won't clip content anymore)
- Accordion: use stable key (index+question) instead of filtered array
  index — search+toggle no longer opens wrong item

src/pages/AdminInfoPages.tsx

@@ -324,7 +324,7 @@ export default function AdminInfoPages() {
       </div>
 
       {/* Filter tabs */}
-      <div className="flex gap-1">
+      <div className="flex flex-wrap gap-1">
         {(['all', 'page', 'faq'] as const).map((tab) => (
           <button
             key={tab}