fix: resolve JavaScript module import error in test app

- Replace ES module imports with global Capacitor objects
- Add null checks for DailyNotification plugin availability
- Fix 'Failed to resolve module specifier @capacitor/core' error
- Use window.Capacitor and window.DailyNotification instead of imports

This resolves the JavaScript error that was preventing the web
interface from loading properly in the test app.

www/index.html

@@ -60,18 +60,21 @@
         </div>
     </div>
 
-    <script type="module">
-        import { Capacitor } from '@capacitor/core';
-        import { DailyNotification } from '@timesafari/daily-notification-plugin';
-
-        window.Capacitor = Capacitor;
-        window.DailyNotification = DailyNotification;
+    <script>
+        // Use global Capacitor and plugin objects instead of ES modules
+        // These are provided by the Capacitor runtime
+        const Capacitor = window.Capacitor;
+        const DailyNotification = window.DailyNotification;
 
         window.testPlugin = async function() {
             const status = document.getElementById('status');
             status.innerHTML = 'Testing plugin...';
             
             try {
+                if (!DailyNotification) {
+                    status.innerHTML = 'DailyNotification plugin not available';
+                    return;
+                }
                 const result = await DailyNotification.echo({ value: 'Hello from test app!' });
                 status.innerHTML = `Plugin test successful: ${result.value}`;
             } catch (error) {
@@ -84,6 +87,10 @@
             status.innerHTML = 'Configuring plugin...';
             
             try {
+                if (!DailyNotification) {
+                    status.innerHTML = 'DailyNotification plugin not available';
+                    return;
+                }
                 await DailyNotification.configure({
                     fetchUrl: 'https://api.example.com/daily-content',
                     scheduleTime: '09:00',
@@ -100,6 +107,10 @@
             status.innerHTML = 'Checking plugin status...';
             
             try {
+                if (!DailyNotification) {
+                    status.innerHTML = 'DailyNotification plugin not available';
+                    return;
+                }
                 const result = await DailyNotification.getStatus();
                 status.innerHTML = `Plugin status: ${JSON.stringify(result, null, 2)}`;
             } catch (error) {