feat: 添加备案查询链接配置

feat: 更新备案查询链接配置说明

feat: 更新备案链接文本为动态配置

components/BeiAnSite.js

@@ -6,14 +6,15 @@ import { siteConfig } from '@/lib/config'
  */
 export default function BeiAnSite() {
   const beian = siteConfig('BEI_AN')
+  const beianLink = siteConfig('BEI_AN_LINK')
   if (!beian) {
     return null
   }
   return (
     <span>
       <i className='fas fa-shield-alt' />
-      <a href='https://beian.miit.gov.cn/' className='mx-1'>
-        {siteConfig('BEI_AN')}
+      <a href={beianLink} className='mx-1'>
+        {beian}
       </a>
       <br />
     </span>