add postmortem (#241)

apps/marketing/next.config.js

@@ -1,3 +1,5 @@
+import createMDX from "@next/mdx";
+
 /** @type {import("next").NextConfig} */
 const config = {
   // Use static export in production by default; keep dev server dynamic
@@ -6,6 +8,11 @@ const config = {
     // Required for static export if using images
     unoptimized: true,
   },
+  pageExtensions: ["js", "jsx", "md", "mdx", "ts", "tsx"],
 };
 
-export default config;
+const withMDX = createMDX({
+  extension: /\.(md|mdx)$/,
+});
+
+export default withMDX(config);