Update favicon to custom png

public/index.html

@@ -4,7 +4,7 @@
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>TokenWatch - API Limit Tracker</title>
-    <link rel="icon" type="image/jpeg" href="favicon.jpg">
+    <link rel="icon" type="image/png" href="favicon.png">
     <link rel="stylesheet" href="style.css">
     <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>
     <script src="https://cdn.jsdelivr.net/npm/canvas-confetti@1.6.0/dist/confetti.browser.min.js"></script>