added random cybersigilism generation

frontend/src/components/react/PostList.tsx

@@ -1,6 +1,23 @@
 import { useEffect, useRef, useState } from 'react';
 import { deletePost } from '../../lib/api';
 import { confirmDialog, notify } from '../../lib/confirm';
+import { buildCybersigil } from '../../lib/cybersigil';
+
+// Per-plate sigil accent. Built post-mount (not during render) so the random
+// markup never differs between SSR and hydration. Inert/display:none off the
+// cybersigil theme; carves in on plate hover/focus via global.css.
+function PlateSigil() {
+  const [html, setHtml] = useState('');
+  useEffect(() => { setHtml(buildCybersigil()); }, []);
+  if (!html) return null;
+  return (
+    <div
+      className="cs-plate-sig"
+      aria-hidden="true"
+      dangerouslySetInnerHTML={{ __html: html }}
+    />
+  );
+}
 
 const PAGE_SIZE = 9;
 
@@ -220,6 +237,8 @@ export default function PostList({ posts: initialPosts, isAdmin = false }: Props
                 </button>
               </div>
             )}
+
+            <PlateSigil />
           </article>
         );
       })}