feat: add sitemap file

app/sitemap.ts

@@ -0,0 +1,36 @@
+import type { MetadataRoute } from "next";
+
+import { BASE_PATH, BASE_URL } from "@/next.constants.mjs";
+
+// This is the combination of the Application Base URL and Base PATH
+const baseUrlAndPath = `${BASE_URL}${BASE_PATH}`;
+
+// This allows us to generate a `sitemap.xml` file dynamically based on the needs of the Node.js Website
+// Next.js Sitemap Generation doesn't support `alternate` refs yet
+// @see https://github.com/vercel/next.js/discussions/55646
+const sitemap = async (): Promise<MetadataRoute.Sitemap> => {
+  const staticUrls = [
+    "",
+    "legal/terms",
+    "legal/support-terms",
+    "legal/sla",
+    "legal/privacy-policy",
+    "sign-in",
+    "sign-up",
+    "about",
+    "help",
+  ];
+  const currentDate = new Date().toISOString();
+
+  return [...staticUrls].map((route) => ({
+    url: `${baseUrlAndPath}${route}`,
+    lastModified: currentDate,
+    changeFrequency: "always",
+  }));
+};
+
+export default sitemap;
+
+// Enforces that this route is used as static rendering
+// @see https://nextjs.org/docs/app/api-reference/file-conventions/route-segment-config#dynamic
+export const dynamic = "error";