[Phase 5 U3] Mount TMDBFooter in public layout

Wraps the (public) route group in a flex-column layout that pushes the
existing TMDBFooter component to the bottom on landing and privacy
pages, satisfying TMDB attribution requirements. Reuses the styled
component as-is.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/app/(public)/layout.tsx

@@ -1,3 +1,10 @@
+import { TMDBFooter } from "@/components/shared/tmdb-footer";
+
 export default function PublicLayout({ children }: { children: React.ReactNode }) {
-  return <>{children}</>;
+  return (
+    <div className="flex min-h-screen flex-col">
+      <div className="flex-1">{children}</div>
+      <TMDBFooter />
+    </div>
+  );
 }