Revise README project description for clarity

Updated project description to highlight customization and compatibility.

Author: beacoder

README.md

@@ -2,7 +2,7 @@
 
 # python-agent-harness
 
-**A lightweight Python coding-agent harness for reliable autonomous coding.**  
+**A mini-OpenCode written in Python — lightweight, hackable, and easy to customize.**  
 FSM-driven execution · OpenAI-compatible · built for daily use and easy customization
 
 [![CI](https://github.com/beacoder/python-agent-harness/actions/workflows/ci.yml/badge.svg)](https://github.com/beacoder/python-agent-harness/actions/workflows/ci.yml)