seo fixes

public/index.html

@@ -11,7 +11,7 @@
   <script defer src="./app.js"></script>
 
   <button id="cw-chatToggle" aria-label="Toggle chat widget" type="button">
-    <img src="logo.svg"><span class="text-xs">Agent</span>
+    <img src="logo.svg" alt="Logo"><span class="text-xs">Agent</span>
   </button>
 
   <div id="cw-chatWidget" role="region" aria-live="polite" aria-label="Customer support chat widget">
@@ -345,4 +345,4 @@
 <script defer src="./app.js"></script>
 
 </body>
-</html>
+</html>