fix(layout): align /category main padding with /browse

Both routes render the same MessageStream; the layout wrapper used to inset
/category by px-4 / sm:px-6 on mobile while /browse stayed edge-to-edge,
shrinking bubble width and making the category waterfall feel narrower
than the all-resources page.

src/layouts/PublicLayout.tsx

@@ -329,7 +329,14 @@ export function PublicLayout() {
       });
     }
   };
-  const footerInContentFlow = stripLangPrefix(pathname) === "/browse";
+  // Routes that render a full-bleed asset stream and manage their own inner
+  // width / padding via `MessageStream`. Both 全部资料 (/browse) and the
+  // per-category view (/category/<slug>) reuse the same component, so they
+  // need the same zero outer padding here — otherwise the category page's
+  // bubbles render narrower than the all-resources page.
+  const strippedPath = stripLangPrefix(pathname);
+  const footerInContentFlow =
+    strippedPath === "/browse" || strippedPath.startsWith("/category/");
   // Current page name shown in the header brand slot (falls back to the brand).
   const pageTitle = usePageTitle();