fix: Resolve daily-notification test suite issues

- Fix test structure to use DailyNotification class with mocks
- Add proper validation for required URL parameter
- Fix event handler error handling in setupEventListeners
- Update all tests to use mock plugin instead of Capacitor plugin
- Add comprehensive validation tests for URL, time, timezone, retry settings
- All 18 daily-notification tests now passing

src/daily-notification.ts

@@ -142,13 +142,20 @@ export class DailyNotification {
   private setupEventListeners(): void {
     document.addEventListener('notification', (event: Event) => {
       this.eventListeners.get('notification')?.forEach(handler => {
-        handler(event);
+        try {
+          handler(event);
+        } catch (error) {
+          console.error('Error in event handler:', error);
+        }
       });
     });
   }
 
   private validateOptions(options: NotificationOptions): void {
-    if (options.url && !this.isValidUrl(options.url)) {
+    if (!options.url) {
+      throw new Error('URL is required');
+    }
+    if (!this.isValidUrl(options.url)) {
       throw new Error('Invalid URL format');
     }
     if (options.time && !this.isValidTime(options.time)) {