Revise README for better overview and organization

Updated the README to improve clarity and structure.

Author: azhong-git

README.md

@@ -16,18 +16,17 @@
     <img src="https://img.shields.io/github/license/lightfeed/browser-agent" alt="License" /></a>
 </div>
 
-## Why
-
-`@lightfeed/browser-agent` is a TypeScript library for building browser agents whose main value prop is **cutting LLM tokens on every rerun**.
+## Overview
+`@lightfeed/browser-agent` is a TypeScript browser agent library built for cutting LLM token use on every rerun.
 
 Most browser-agent work has two parts:
 
 - **Navigation** — many clicks / types / scrolls to reach a target page. Most of the steps, most of the tokens, usually the same every run if the page structure is stable. Today's agents pay for these tokens *every single time*.
 - **Extraction** — pull typed data out of whatever is on screen. Must re-run AI each time because the content is live.
 
-This library lets you run navigation once with AI, save it as a plan, and **replay it with zero LLM calls** — no screenshots, no DOM map, no tokens. Then run a cheap `.extract()` on the result page for the dynamic tail. If the DOM drifts, optional `aiFallback` re-plans **only the broken step**, so you still pay tokens for a fraction of the flow instead of all of it.
+**This library lets you run navigation once with AI, save it as a plan, and replay it with zero LLM calls** — no screenshots, no DOM map, no tokens. Then run a cheap `.extract()` on the result page for the dynamic tail. If the DOM drifts, optional `aiFallback` re-plans **only the broken step**, so you still pay tokens for a fraction of the flow instead of all of it.
 
-Runs anywhere your browser lives — the same `BrowserAgent` API drives a **local** Chromium for dev, a **serverless** Chromium (AWS Lambda via `@sparticuz/chromium`) for scheduled jobs, or a **remote** CDP endpoint (Brightdata Scraping Browser, any browser farm, or your own). Swap backends by changing one config field; prompts, plans, and `.extract()` calls stay identical.
+**Runs anywhere your browser lives** — the same `BrowserAgent` API drives a **local** Chromium for dev, a **serverless** Chromium (AWS Lambda via `@sparticuz/chromium`) for scheduled jobs, or a **remote** CDP endpoint (Brightdata Scraping Browser, any browser farm, or your own). Swap backends by changing one config field; prompts, plans, and `.extract()` calls stay identical.
 
 ## Install