Clarify project purpose in README

Adds a short Project Overview section to explain the scope of the Base Node repository.

Author: yosoyjhork

README.md

@@ -10,6 +10,12 @@ Base is a secure, low-cost, developer-friendly Ethereum L2 built on Optimism's [
 [![Twitter Base](https://img.shields.io/twitter/follow/Base?style=social)](https://x.com/Base)
 [![Farcaster Base](https://img.shields.io/badge/Farcaster_Base-3d8fcc)](https://farcaster.xyz/base)
 
+## Project Overview
+
+This repository contains the reference implementation of the Base Node,
+focused on running, operating, and maintaining the Base network infrastructure.
+
+
 ## Quick Start
 
 1. Ensure you have an Ethereum L1 full node RPC available