chore: import upstream snapshot with attribution

fixtures/node-env/src/index.ts

@@ -0,0 +1,20 @@
+import React from "react";
+import { renderToString } from "react-dom/server";
+
+export default {
+	async fetch(request) {
+		const url = new URL(request.url);
+
+		if (url.pathname === "/ssr") {
+			const content = renderToString(
+				React.createElement("h1", null, "Hello world")
+			);
+
+			return new Response(content);
+		}
+
+		return new Response(
+			`The value of process.env.NODE_ENV is "${process.env.NODE_ENV}"`
+		);
+	},
+} satisfies ExportedHandler;