Add site information management with Markdown support

frontend/index.html

@@ -35,6 +35,7 @@
     <script>
       window.serverName = "{{SiteName}}";
       window.cloudflareTurnstileSiteKey = "{{CFTurnstileSiteKey}}";
+      window.siteInfo = `{{SiteInfo}}`;
     </script>
     <div id="root"></div>
     <script type="module" src="/src/main.tsx"></script>