feat: clear btn in web

web/index.html

@@ -45,6 +45,7 @@
         <button id="token2">Token btn 2</button>
         <button id="colorChangeBtnRed">Color btn Red</button>
         <button id="colorChangeBtnBlue">Color btn Blue</button>
+        <button id="clearBtn">Clear</button>
         <section class="contents">
             <article>
                 <div id="flutter_target"></div>

web/js/demo-js-interop.js

@@ -53,6 +53,11 @@
             var numColor = parseInt(hexColor, 16);
             appState.changeColor(numColor, false);
         });
+        let clearBtn = document.getElementById('clearBtn');
+        clearBtn.addEventListener('click', function () {
+            localStorage.clear();
+            window.location.reload();
+        });
 
         function onError() {
             console.error('aboba');