Update README.md with live demo link

Added a link to the live deployed version on Render. This helps users preview the project directly without running it locally.

Author: Syntax-Vibe-Amir

README.md

@@ -1,5 +1,7 @@
 # 🖥️ System Health Dashboard
 
+🔗 **Live Demo**: [https://system-health-dashboard.onrender.com](https://system-health-dashboard.onrender.com)
+
 A lightweight Flask-based dashboard to monitor your system's real-time health — including **CPU**, **RAM**, **Disk usage**, and **system time** — all containerized with **Docker** and powered by **GitHub Actions CI**.
 
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