feat(docs): add comprehensive SEO optimization for static docs site

Add per-page metadata, Open Graph / Twitter tags, canonical URLs,
hreflang, sitemap generation, robots.txt, and JSON-LD structured data
for the bilingual (en/cn) documentation site.

docs/app/[lang]/changelog/page.tsx

@@ -1,6 +1,8 @@
 import { LandingNav } from '@/components/landing/LandingNav';
 import { ChangelogRuntime } from '@/components/landing/ChangelogRuntime';
 import { fetchChangelog } from '@/lib/changelog';
+import { buildMetadata } from '@/lib/metadata';
+import type { Metadata } from 'next';
 
 const i18n = {
   en: {
@@ -13,6 +15,23 @@ const i18n = {
   },
 };
 
+export async function generateMetadata({
+  params,
+}: {
+  params: Promise<{ lang: string }>;
+}): Promise<Metadata> {
+  const { lang } = await params;
+  const l = lang === 'cn' ? 'cn' : 'en';
+  const t = i18n[l];
+
+  return buildMetadata({
+    title: t.title,
+    description: t.desc,
+    path: `/${l}/changelog`,
+    lang: l,
+  });
+}
+
 export default async function ChangelogPage({ params }: { params: Promise<{ lang: string }> }) {
   const { lang } = await params;
   const l = lang === 'cn' ? 'cn' : 'en';

docs/app/[lang]/community/page.tsx

@@ -1,4 +1,6 @@
 import { LandingNav } from '@/components/landing/LandingNav';
+import { buildMetadata } from '@/lib/metadata';
+import type { Metadata } from 'next';
 
 const channels = [
   {
@@ -58,6 +60,23 @@ const i18n = {
   },
 };
 
+export async function generateMetadata({
+  params,
+}: {
+  params: Promise<{ lang: string }>;
+}): Promise<Metadata> {
+  const { lang } = await params;
+  const l = lang === 'cn' ? 'cn' : 'en';
+  const t = i18n[l];
+
+  return buildMetadata({
+    title: t.title,
+    description: t.desc,
+    path: `/${l}/community`,
+    lang: l,
+  });
+}
+
 export default async function CommunityPage({ params }: { params: Promise<{ lang: string }> }) {
   const { lang } = await params;
   const l = lang === 'cn' ? 'cn' : 'en';

docs/app/[lang]/docs/[[...slug]]/page.tsx

@@ -1,5 +1,6 @@
 import { source } from '@/lib/source';
 import { notFound } from 'next/navigation';
+import type { Metadata } from 'next';
 import {
   DocsPage,
   DocsBody,
@@ -15,6 +16,28 @@ import { ImageZoom } from 'fumadocs-ui/components/image-zoom';
 import { Accordion, Accordions } from 'fumadocs-ui/components/accordion';
 import type { MDXContent } from 'mdx/types';
 import type { TOCItemType } from 'fumadocs-core/toc';
+import { buildMetadata, SITE_URL } from '@/lib/metadata';
+
+export async function generateMetadata({
+  params,
+}: {
+  params: Promise<{ lang: string; slug?: string[] }>;
+}): Promise<Metadata> {
+  const { lang, slug } = await params;
+  const page = source.getPage(slug, lang);
+  if (!page) return {};
+
+  const title = page.data.title as string;
+  const description = (page.data.description as string) || undefined;
+
+  return buildMetadata({
+    title,
+    description: description ?? '',
+    path: slug ? `/${lang}/docs/${slug.join('/')}` : `/${lang}/docs`,
+    lang,
+    ogType: 'article',
+  });
+}
 
 const mdxComponents = {
   ...defaultMdxComponents,
@@ -44,10 +67,51 @@ export default async function Page({
     toc: TOCItemType[];
   };
 
+  const title = page.data.title as string;
+  const description = (page.data.description as string) || '';
+  const docPath = slug ? `/${lang}/docs/${slug.join('/')}` : `/${lang}/docs`;
+
+  const breadcrumbJsonLd = {
+    '@context': 'https://schema.org',
+    '@type': 'BreadcrumbList',
+    itemListElement: [
+      { '@type': 'ListItem', position: 1, name: 'Home', item: SITE_URL },
+      { '@type': 'ListItem', position: 2, name: 'Docs', item: `${SITE_URL}/${lang}/docs` },
+      ...(slug
+        ? slug.map((segment, i) => ({
+            '@type': 'ListItem' as const,
+            position: i + 3,
+            name: segment.replace(/-/g, ' ').replace(/\b\w/g, (c) => c.toUpperCase()),
+            item: `${SITE_URL}/${lang}/docs/${slug.slice(0, i + 1).join('/')}`,
+          }))
+        : []),
+    ],
+  };
+
+  const articleJsonLd = {
+    '@context': 'https://schema.org',
+    '@type': 'TechArticle',
+    headline: title,
+    description,
+    inLanguage: lang === 'cn' ? 'zh-CN' : 'en',
+    isPartOf: {
+      '@type': 'WebSite',
+      url: SITE_URL,
+    },
+  };
+
   return (
     <DocsPage toc={toc}>
-      <DocsTitle>{page.data.title}</DocsTitle>
-      <DocsDescription>{page.data.description}</DocsDescription>
+      <script
+        type="application/ld+json"
+        dangerouslySetInnerHTML={{ __html: JSON.stringify(breadcrumbJsonLd) }}
+      />
+      <script
+        type="application/ld+json"
+        dangerouslySetInnerHTML={{ __html: JSON.stringify(articleJsonLd) }}
+      />
+      <DocsTitle>{title}</DocsTitle>
+      <DocsDescription>{description}</DocsDescription>
       <DocsBody>
         <MDX components={mdxComponents} />
       </DocsBody>

docs/app/[lang]/layout.tsx

@@ -1,6 +1,52 @@
 import type { ReactNode } from 'react';
+import type { Metadata } from 'next';
 import { RootProvider } from 'fumadocs-ui/provider/next';
 import { i18nUI } from '@/lib/i18n';
+import { SITE_URL, SITE_NAME, DEFAULT_DESCRIPTION } from '@/lib/metadata';
+
+const LOCALE_MAP: Record<string, { locale: string; title: string; description: string }> = {
+  en: {
+    locale: 'en_US',
+    title: 'DBX - 15 MB to manage 35+ databases',
+    description: DEFAULT_DESCRIPTION,
+  },
+  cn: {
+    locale: 'zh_CN',
+    title: 'DBX - 15MB，管理35+种数据库',
+    description: '25+ 种数据库，仅 15 MB。支持桌面与 Docker 自托管，内置 AI 助手。',
+  },
+};
+
+export async function generateMetadata({
+  params,
+}: {
+  params: Promise<{ lang: string }>;
+}): Promise<Metadata> {
+  const { lang } = await params;
+  const l = lang === 'cn' ? 'cn' : 'en';
+  const meta = LOCALE_MAP[l];
+
+  return {
+    title: {
+      default: meta.title,
+      template: `%s | ${SITE_NAME}`,
+    },
+    description: meta.description,
+    openGraph: {
+      locale: meta.locale,
+      siteName: SITE_NAME,
+      url: `${SITE_URL}/${l}`,
+    },
+    alternates: {
+      canonical: `${SITE_URL}/${l}`,
+      languages: {
+        en: `${SITE_URL}/en`,
+        zh: `${SITE_URL}/cn`,
+        'x-default': `${SITE_URL}/en`,
+      },
+    },
+  };
+}
 
 export default async function LangLayout({
   params,

docs/app/[lang]/page.tsx

@@ -1,4 +1,5 @@
 import Link from 'next/link';
+import type { Metadata } from 'next';
 import type { CSSProperties } from 'react';
 import { HeroProductStage } from '@/components/aceternity/HeroProductStage';
 import { InfiniteMovingCards } from '@/components/aceternity/InfiniteMovingCards';
@@ -366,6 +367,39 @@ const i18nText = {
   },
 };
 
+import { buildMetadata } from '@/lib/metadata';
+
+const landingMeta = {
+  en: {
+    title: 'DBX - 15 MB to manage 35+ databases!',
+    description:
+      'DBX brings connections, SQL editing, data grids, schema tools, AI assistance, and self-hosted access into one lightweight product.',
+  },
+  cn: {
+    title: 'DBX - 15MB，管理35+种数据库！',
+    description:
+      'DBX 将连接管理、SQL 编辑、数据表格、结构工具、AI 助手和自托管访问放进一个轻量产品里。',
+  },
+};
+
+export async function generateMetadata({
+  params,
+}: {
+  params: Promise<{ lang: string }>;
+}): Promise<Metadata> {
+  const { lang } = await params;
+  const l = lang === 'cn' ? 'cn' : 'en';
+  const meta = landingMeta[l];
+
+  return buildMetadata({
+    title: meta.title,
+    description: meta.description,
+    path: `/${l}`,
+    lang: l,
+    ogType: 'website',
+  });
+}
+
 export default async function LandingPage({
   params,
 }: {

docs/app/layout.tsx

@@ -1,22 +1,54 @@
 import './global.css';
 import type { ReactNode } from 'react';
+import type { Metadata } from 'next';
+import { SITE_URL, SITE_NAME, DEFAULT_DESCRIPTION, DEFAULT_OG_IMAGE } from '@/lib/metadata';
 
-export const metadata = {
+export const metadata: Metadata = {
   title: {
-    default: 'DBX',
-    template: '%s | DBX',
+    default: SITE_NAME,
+    template: `%s | ${SITE_NAME}`,
   },
-  description: '25+ databases in 15 MB. Desktop & Docker self-hosting, with built-in AI assistant.',
+  description: DEFAULT_DESCRIPTION,
+  metadataBase: new URL(SITE_URL),
   icons: {
     icon: '/favicon.png',
     shortcut: '/favicon.png',
     apple: '/logo.png',
   },
+  openGraph: {
+    siteName: SITE_NAME,
+    images: [{ url: DEFAULT_OG_IMAGE }],
+  },
+  twitter: {
+    card: 'summary_large_image',
+  },
 };
 
 export default function RootLayout({ children }: { children: ReactNode }) {
   return (
-    <html lang="en" className="dark" suppressHydrationWarning>
+    <html className="dark" suppressHydrationWarning>
+      <head>
+        <script
+          type="application/ld+json"
+          dangerouslySetInnerHTML={{
+            __html: JSON.stringify({
+              '@context': 'https://schema.org',
+              '@type': 'WebSite',
+              name: SITE_NAME,
+              url: SITE_URL,
+              description: DEFAULT_DESCRIPTION,
+              potentialAction: {
+                '@type': 'SearchAction',
+                target: {
+                  '@type': 'EntryPoint',
+                  urlTemplate: `${SITE_URL}/search?q={search_term_string}`,
+                },
+                'query-input': 'required name=search_term_string',
+              },
+            }),
+          }}
+        />
+      </head>
       <body className="flex min-h-screen flex-col">{children}</body>
     </html>
   );