feat: enable sitemap (#74)

Author: flemay

astro.config.mjs

@@ -7,6 +7,7 @@ const githubUrl = "https://github.com/flemay/3musketeers";
 // https://astro.build/config
 // https://starlight.astro.build/reference/configuration/
 export default defineConfig({
+  site: "https://3musketeers.pages.dev",
   integrations: [
     starlight({
       title: "3 Musketeers",