add async hooks example

samples/node-async-hooks/node-async-hooks.js

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+import { AsyncLocalStorage } from "node:async_hooks";
+
+const requestId = new AsyncLocalStorage();
+
+async function logAsyncContext(state) {
+    console.log(`${requestId.getStore()} - ${state}`);
+}
+
+async function doSomething() {
+    logAsyncContext("log from async function");
+    doSomethingElse();
+}
+
+async function doSomethingElse() {
+    logAsyncContext("log from another async function");
+}
+
+async function handleRequest(request) {
+    const id = request.headers.get("X-Request-Id");
+
+    return requestId.run(id, async () => {
+        doSomething();
+        logAsyncContext("log from yet another async function");
+        requestId.exit(async () => {
+            logAsyncContext("log from exit callback");
+        });
+        return new Response("ok");
+    });
+}
+
+addEventListener("fetch", (event) => {
+    event.respondWith(handleRequest(event.request));
+});

samples/node-async-hooks/readme.md

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+# Node.js Async Hooks and Edge Functions
+
+This is an example of using **Node.js Async Hooks**, specifically the **AsyncLocalStorage API**, to manage context within asynchronous operations inside an edge function.
+
+## Code Overview
+
+The code consists of several asynchronous functions (**doSomething**, **doSomethingElse**, **handleRequest**) that simulate different parts of a request-handling process.
+
+The AsyncLocalStorage instance, **requestId**, is used to store and retrieve a request-specific value (in this case, a request ID from headers) across these asynchronous operations.
+
+Here's a brief description of the functions:
+
+- logAsyncContext(state): logs the current request ID and a state message to the console.
+- doSomething(): simulates an asynchronous operation and logs its context.
+- doSomethingElse(): simulates another asynchronous operation and logs its context.
+- handleRequest(request): handles an incoming request, retrieves the request ID from the headers, and runs a series of asynchronous operations within the context of this request ID.
+
+The handleRequest function is registered as an event listener for fetch events, meaning it'll be invoked for every incoming request.
+
+## Usage
+
+This code is designed to run on **Azion Edge Runtime** and demonstrates how to use AsyncLocalStorage to maintain context across asynchronous operations. It can be particularly useful in scenarios such as request handling in a web server, where you might need to keep track of request-specific data across multiple asynchronous operations.