Add experimental status notice to README

- Add clear warning about experimental development status at the top of README
- Recommend careful consideration before using in production
- Add visual status badge in the heading section for visibility
- Keep existing content and project description intact

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: kmmbvnr

README.md

@@ -1,4 +1,4 @@
-# Django Material 3
+> **⚠️ IMPORTANT:** This project is currently in experimental development status. APIs, components, and functionality may change significantly between versions. While it's suitable for exploration and prototyping, we recommend careful consideration before using in production environments.
 
 <div align="center">
   <a href="https://github.com/viewflow/django-material">
@@ -8,6 +8,8 @@
   <h3 align="center">Django Material Design 3</h3>
 
   <p align="center">
+    <span><img src="https://img.shields.io/badge/Status-Experimental-yellow" alt="Status: Experimental"></span>
+    <br />
     Modern Material Design components for Django
     <br />
     <a href="https://material.viewflow.io"><strong>Explore the docs »</strong></a>