Fix Documentation: Incorrect imports and export in examples/external_client.js

[GODCREATOR333]

Issue Description

The example code in examples/external_client.js contains incorrect import paths that need to be updated to match the current package structure.

Current (Incorrect) Code:-

import { Stagehand } from "@/dist";
import { z } from "zod";
import { OllamaClient } from "./external_clients/ollama";
import StagehandConfig from "@/stagehand.config";

Corrected Code:-

import { Stagehand } from "@browserbasehq/stagehand";
import { z } from "zod";
import { OllamaClient } from "./ollama_client.js";
import StagehandConfig from "./stagehand.config.js";

The function example() is not being exported correctly to be used in main.ts or index.ts.
Someone with the right permissions may assign me this task as i would like to make a PR.