移除旧版 HTML 模板与兼容层，并完善私信、举报、媒体存储与 SEO。

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/components/FeaturedIcon.tsx

@@ -0,0 +1,19 @@
+import { Sparkles } from 'lucide-react';
+import { cn } from '@/lib/utils';
+
+interface Props {
+  className?: string;
+  size?: number;
+}
+
+/** 精华帖标识 */
+export default function FeaturedIcon({ className, size = 16 }: Props) {
+  return (
+    <Sparkles
+      className={cn('post-featured-icon', className)}
+      size={size}
+      aria-label="精华"
+      role="img"
+    />
+  );
+}