update README

Added a header and quickstart section to README.

Author: fraware

README.md

@@ -1,7 +1,13 @@
+<div align="center">
+
 # Lean 4 CI on Morph Cloud
 
 A minimal, reusable CI template for running Lean 4 proofs on Morph Cloud's Infinibranch with intelligent caching and sharding.
 
+</div>
+
+---
+
 ## Quickstart
 
 1. **Fork the Repository**: Click the 'Fork' button at the top-right of this page.