完善站点运营设置：分路由管理、登录可见评论、邮件模板内联与关闭注册 SSR。

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

frontend/app/layout.tsx

@@ -1,3 +1,4 @@
+import OperationalBanner from "@/components/OperationalBanner";
 import type { Metadata } from "next";
 import { cookies, headers } from "next/headers";
 import { Plus_Jakarta_Sans, Noto_Sans_SC, JetBrains_Mono } from "next/font/google";
@@ -22,7 +23,8 @@ import { accentStyleCSS } from "@/lib/theme";
 import { bgConfigFromSettings, bgStyleCSS } from "@/lib/bg";
 import { siteDocumentTitle } from "@/lib/brand";
 import { motionConfigFromSettings } from "@/lib/motion";
-import { requestMetadataBase } from "@/lib/canonicalMeta";
+import { peekPublicMetaSnapshot, publishPublicMetaSnapshot } from "@/lib/publicMetaSnapshot";
+import { metadataBaseURL } from "@/lib/siteUrl";
 
 // 构建期下载并自托管字体：同源加载 + 自动 preload + fallback 度量校正，
 // 消除 F5 时 Google CDN 字体到达后整页"由粗变细"的 FOUT 闪动
@@ -47,15 +49,16 @@ const jetbrainsMono = JetBrains_Mono({
   display: "swap",
 });
 
-export async function generateMetadata(): Promise<Metadata> {
-  const settings = await getPublicSettingsCached();
+// 必须同步：根 layout 若在此 await（拉设置 / headers），Next 流式 metadata
+// 会在等待期把标签临时写成 localhost:3000，开发态 RSC/HMR 一密就来回闪。
+export function generateMetadata(): Metadata {
+  const settings = peekPublicMetaSnapshot();
   const name = settings.site_name || "姜十三论坛";
   const title = siteDocumentTitle(name, settings.site_slogan || "");
   const desc = settings.site_description || "姜十三论坛 - 技术分享与讨论社区";
   const keywords = settings.site_keywords?.length ? settings.site_keywords : undefined;
-  const metadataBase = await requestMetadataBase();
+  const metadataBase = metadataBaseURL();
   return {
-    // 只提供解析相对 URL 的基址；Canonical 由各公开页自行声明，避免子路由继承首页
     ...(metadataBase ? { metadataBase } : {}),
     title: {
       default: title,
@@ -63,9 +66,7 @@ export async function generateMetadata(): Promise<Metadata> {
     },
     description: desc,
     keywords,
-    ...(settings.favicon_url
-      ? { icons: { icon: settings.favicon_url } }
-      : {}),
+    ...(settings.favicon_url ? { icons: { icon: settings.favicon_url } } : {}),
     openGraph: {
       title,
       description: desc,
@@ -94,6 +95,7 @@ export default async function RootLayout({
   // 站点主题色（公开设置）：派生浅/暗两套 accent CSS 变量后随首屏 HTML 内联，
   // 覆盖 globals.css 默认令牌——无主题闪动（FOUC），后端不可用时降级为默认靛蓝
   const settings = await getPublicSettingsCached();
+  publishPublicMetaSnapshot(settings);
   const accent = settings.accent;
   const accentCSS = accentStyleCSS(accent || "");
   const bgCfg = bgConfigFromSettings(settings);
@@ -147,7 +149,10 @@ export default async function RootLayout({
         </a>
         <SiteBrandProvider initial={settings}>
         <MotionProvider initial={motionCfg}>
-          <CommentsPolicyProvider allowComments={settings.allow_comments !== false}>
+          <CommentsPolicyProvider
+            allowComments={settings.allow_comments !== false}
+            requireLogin={settings.comments_require_login === true}
+          >
             <MessagesPolicyProvider allowMessages={settings.allow_messages !== false}>
               <PostLinkProvider openInNewTab={settings.post_link_new_tab !== false}>
                 <CodeFoldProvider
@@ -160,8 +165,8 @@ export default async function RootLayout({
                     unread={unread}
                     chatUnread={settings.allow_messages !== false ? chatUnread : 0}
                     theme={theme}
-                    allowRegister={settings.allow_register}
                   >
+                    <OperationalBanner />
                     {children}
                   </SiteChrome>
                 </CodeFoldProvider>