Add usage script

src/Header.jsx

@@ -1,11 +1,18 @@
-import React from 'react';
+import React, { useEffect } from 'react';
 
 function Header() {
-  return (
-    <header>
-      <script defer data-domain="github-copilot.xebia.ms" src="https://plausible.io/js/script.js"></script>
-    </header>
-  );
+  useEffect(() => {
+    const script = document.createElement('script');
+    script.src = "https://plausible.io/js/plausible.js";
+    script.setAttribute('data-domain', 'github-copilot.xebia.ms');
+    document.head.appendChild(script);
+
+    return () => {
+      document.head.removeChild(script);
+    };
+  }, []);
+
+  return null;
 }
 
 export default Header;