listThreads snippet update (Azure#33984)

### Packages impacted by this PR


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### Describe the problem that is addressed by this PR
updating snippet to match sample change

### What are the possible designs available to address the problem? If
there are more than one possible design, why was the one in this PR
chosen?


### Are there test cases added in this PR? _(If not, why?)_


### Provide a list of related PRs _(if any)_


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### Checklists
- [ ] Added impacted package name to the issue description
- [ ] Does this PR needs any fixes in the SDK Generator?** _(If so,
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---------

Co-authored-by: Zachary King <[email protected]>

Author: ZachhK

sdk/ai/ai-projects/README.md

@@ -476,7 +476,14 @@ const thread = await client.agents.createThread({ toolResources: fileSearchTool.
 To list all threads attached to a given agent, use the list_threads API:
 
 ```ts snippet:listThreads
-const threads = client.agents.listThreads();
+const threads = await client.agents.listThreads();
+console.log(`Threads for agent ${agent.id}:`);
+for await (const t of (await threads).data) {
+  console.log(`Thread ID: ${t.id}`);
+  console.log(`Created at: ${t.createdAt}`);
+  console.log(`Metadata: ${t.metadata}`);
+  console.log(`---- `);
+}
 ```
 
 #### Create Message

sdk/ai/ai-projects/test/snippets.spec.ts

@@ -17,18 +17,15 @@ import {
   MessageStreamEvent,
   RunStreamEvent,
   ThreadRunOutput,
+  MessageContentOutput,
+  isOutputOfType,
+  MessageTextContentOutput,
+  MessageImageFileContentOutput,
 } from "@azure/ai-projects";
 import { createProjectsClient } from "./public/utils/createClient.js";
 import { DefaultAzureCredential } from "@azure/identity";
 import { beforeEach, it, describe } from "vitest";
 import * as fs from "fs";
-import path from "node:path";
-import {
-  MessageContentOutput,
-  isOutputOfType,
-  MessageTextContentOutput,
-  MessageImageFileContentOutput,
-} from "../src/index.js";
 import { delay } from "@azure/core-util";
 import { trace } from "@opentelemetry/api";
 import { AzureMonitorTraceExporter } from "@azure/monitor-opentelemetry-exporter";
@@ -358,7 +355,14 @@ describe("snippets", function () {
   });
 
   it("listThreads", async function () {
-    const threads = client.agents.listThreads();
+    const threads = await client.agents.listThreads();
+    console.log(`Threads for agent ${agent.id}:`);
+    for await (const t of (await threads).data) {
+      console.log(`Thread ID: ${t.id}`);
+      console.log(`Created at: ${t.createdAt}`);
+      console.log(`Metadata: ${t.metadata}`);
+      console.log(`---- `);
+    }
   });
 
   it("createMessage", async function () {