feat: add SharePanel component for social sharing with QR code support

- Implemented SharePanel component in `SharePanel.astro` for sharing content on social media platforms.
- Integrated QR code generation for WeChat sharing using the `qrcode` library.
- Added localization support for English and Chinese languages.
- Created utility functions in `seo.ts` for building article summaries and FAQs.
- Introduced API routes for serving IndexNow key and generating full LLM catalog and summaries.
- Enhanced SEO capabilities with structured data for articles and pages.

frontend/scripts/submit-indexnow.mjs

@@ -0,0 +1,134 @@
+const DEFAULT_API_PATH = '/api'
+const INDEXNOW_ENDPOINT = 'https://api.indexnow.org/indexnow'
+
+function normalizeBase(value) {
+  return String(value || '').trim().replace(/\/$/, '')
+}
+
+function ensureAbsolute(base, path) {
+  return `${normalizeBase(base)}${String(path).startsWith('/') ? path : `/${path}`}`
+}
+
+async function fetchJson(url) {
+  const response = await fetch(url, {
+    headers: {
+      Accept: 'application/json',
+    },
+  })
+
+  if (!response.ok) {
+    throw new Error(`Failed to fetch ${url}: ${response.status} ${response.statusText}`)
+  }
+
+  return response.json()
+}
+
+function collectStaticRoutes(siteSettings) {
+  const routes = [
+    '/',
+    '/about',
+    '/articles',
+    '/categories',
+    '/tags',
+    '/timeline',
+    '/reviews',
+    '/friends',
+    '/rss.xml',
+    '/sitemap.xml',
+    '/llms.txt',
+    '/llms-full.txt',
+    '/indexnow-key.txt',
+  ]
+
+  if (siteSettings?.ai_enabled || siteSettings?.ai?.enabled) {
+    routes.push('/ask')
+  }
+
+  return routes
+}
+
+async function main() {
+  const indexNowKey = String(process.env.INDEXNOW_KEY || '').trim()
+  if (!indexNowKey) {
+    throw new Error('Missing INDEXNOW_KEY environment variable.')
+  }
+
+  const configuredSiteUrl = normalizeBase(process.env.SITE_URL || process.env.PUBLIC_SITE_URL || '')
+  const configuredApiBaseUrl = normalizeBase(
+    process.env.INTERNAL_API_BASE_URL || process.env.PUBLIC_API_BASE_URL || '',
+  )
+
+  const bootstrapApiBaseUrl = configuredApiBaseUrl || `${configuredSiteUrl}${DEFAULT_API_PATH}`
+  if (!bootstrapApiBaseUrl) {
+    throw new Error('Missing SITE_URL/PUBLIC_SITE_URL or API base URL for IndexNow submission.')
+  }
+
+  const siteSettings = await fetchJson(`${bootstrapApiBaseUrl}/site_settings`).catch(() => null)
+  const siteUrl = normalizeBase(configuredSiteUrl || siteSettings?.site_url || '')
+  if (!siteUrl) {
+    throw new Error('Unable to determine canonical SITE_URL for IndexNow submission.')
+  }
+
+  const apiBaseUrl = configuredApiBaseUrl || `${siteUrl}${DEFAULT_API_PATH}`
+
+  const [posts, categories, tags, reviews] = await Promise.all([
+    fetchJson(`${apiBaseUrl}/posts`).catch(() => []),
+    fetchJson(`${apiBaseUrl}/categories`).catch(() => []),
+    fetchJson(`${apiBaseUrl}/tags`).catch(() => []),
+    fetchJson(`${apiBaseUrl}/reviews`).catch(() => []),
+  ])
+
+  const urls = new Set(collectStaticRoutes(siteSettings).map((path) => ensureAbsolute(siteUrl, path)))
+
+  for (const post of posts) {
+    if (!post?.slug || post?.noindex === true) continue
+    urls.add(ensureAbsolute(siteUrl, `/articles/${encodeURIComponent(post.slug)}`))
+  }
+
+  for (const category of categories) {
+    const token = category?.slug || category?.name
+    if (!token) continue
+    urls.add(ensureAbsolute(siteUrl, `/categories/${encodeURIComponent(token)}`))
+  }
+
+  for (const tag of tags) {
+    const token = tag?.slug || tag?.name
+    if (!token) continue
+    urls.add(ensureAbsolute(siteUrl, `/tags/${encodeURIComponent(token)}`))
+  }
+
+  for (const review of reviews) {
+    if (!review?.id) continue
+    urls.add(ensureAbsolute(siteUrl, `/reviews/${review.id}`))
+  }
+
+  const payload = {
+    host: new URL(siteUrl).host,
+    key: indexNowKey,
+    keyLocation: ensureAbsolute(siteUrl, '/indexnow-key.txt'),
+    urlList: [...urls],
+  }
+
+  const response = await fetch(INDEXNOW_ENDPOINT, {
+    method: 'POST',
+    headers: {
+      'Content-Type': 'application/json; charset=utf-8',
+    },
+    body: JSON.stringify(payload),
+  })
+
+  const responseText = await response.text().catch(() => '')
+  if (!response.ok) {
+    throw new Error(`IndexNow submission failed: ${response.status} ${response.statusText}\n${responseText}`)
+  }
+
+  console.log(`IndexNow submitted ${payload.urlList.length} URLs for ${siteUrl}`)
+  if (responseText) {
+    console.log(responseText)
+  }
+}
+
+main().catch((error) => {
+  console.error(error instanceof Error ? error.message : error)
+  process.exitCode = 1
+})