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/SiteFooter.tsx

@@ -0,0 +1,70 @@
+import { useSiteBranding } from '../hooks/useSiteBranding';
+import { useMediaQuery } from '../hooks/useTheme';
+import type { FriendLink } from '../api/types';
+
+function FooterSep() {
+  return <span className="site-footer__sep" aria-hidden>·</span>;
+}
+
+/** 站点页脚：版权、Sitemap、友链、备案号 */
+export default function SiteFooter() {
+  const { branding } = useSiteBranding();
+  const year = new Date().getFullYear();
+  const links = Array.isArray(branding.friend_links) ? branding.friend_links : [];
+  const icp = branding.icp_beian?.trim() || '';
+  const icpURL = branding.icp_beian_url?.trim() || 'https://beian.miit.gov.cn/';
+
+  return (
+    <footer className="site-footer">
+      <div className="site-footer__inner">
+        <div className="site-footer__meta">
+          <span className="site-footer__copy">
+            © {year} {branding.name}
+          </span>
+          {branding.slogan?.trim() && (
+            <>
+              <FooterSep />
+              <span className="site-footer__slogan">{branding.slogan.trim()}</span>
+            </>
+          )}
+        </div>
+
+        {(links.length > 0 || icp) && (
+          <nav className="site-footer__nav" aria-label="站点链接">
+            {links.map((link: FriendLink, i) => (
+              <span key={`${link.name}-${link.url}`} className="site-footer__friend">
+                {i > 0 && <FooterSep />}
+                <a href={link.url} target="_blank" rel="noopener noreferrer">
+                  {link.name}
+                </a>
+              </span>
+            ))}
+            {icp && (
+              <>
+                {links.length > 0 && <FooterSep />}
+                <a
+                  href={icpURL}
+                  target="_blank"
+                  rel="noopener noreferrer"
+                  className="site-footer__icp"
+                >
+                  {icp}
+                </a>
+              </>
+            )}
+          </nav>
+        )}
+      </div>
+    </footer>
+  );
+}
+
+/**
+ * 手机端随内容滚动的页脚（放在 .page-wrap / .post-list-scroll 末尾）。
+ * 桌面端返回 null，由 MainLayout 壳层贴底页脚负责。
+ */
+export function InFlowSiteFooter() {
+  const isMobile = useMediaQuery('(max-width: 768px)');
+  if (!isMobile) return null;
+  return <SiteFooter />;
+}