Add intro to README

Author: lostintangent

README.md

@@ -1,4 +1,6 @@
-# 📓 GistPad.dev
+# 📓 gistpad.dev
+
+A web app/PWA for managing and sharing your personal knowledge, daily notes, and reusable prompts, using GitHub Gists + AI. It provides a companion experience to the [GistPad extension](https://aka.ms/gistpad) for VS Code, and the [GistPad MCP server](https://npmjs.com/gistpad-mcp). 
 
 <img width="1933" height="1464" alt="image" src="https://github.com/user-attachments/assets/7ca6a2ba-5c10-43d4-ae29-7316509efb35" />