🐛 fix(header): prevent NotificationButton from shrinking when unread badge appears

- Remove `size='small'` when the button is wrapped by `Badge`
- Keep button dimensions consistent with/without badge
- Preserve 18px icon size and existing styles/accessibility
- Lint check passed with no issues

Files: web/src/components/layout/HeaderBar/NotificationButton.jsx

web/src/components/layout/HeaderBar/NotificationButton.jsx

@@ -34,7 +34,7 @@ const NotificationButton = ({ unreadCount, onNoticeOpen, t }) => {
   if (unreadCount > 0) {
     return (
       <Badge count={unreadCount} type="danger" overflowCount={99}>
-        <Button {...buttonProps} size='small' />
+        <Button {...buttonProps} />
       </Badge>
     );
   }