Add Hello World to README

Added a simple Hello World message to the README.

README.md

@@ -6,6 +6,8 @@
 
 Claude Code is an agentic coding tool that lives in your terminal, understands your codebase, and helps you code faster by executing routine tasks, explaining complex code, and handling git workflows -- all through natural language commands. Use it in your terminal, IDE, or tag @claude on Github.
 
+Hello World
+
 **Learn more in the [official documentation](https://docs.anthropic.com/en/docs/claude-code/overview)**.
 
 <img src="./demo.gif" />