feat: add user preference for audio notifications and play sound on new alerts

- Added sound_enabled column to users table with a default of true.

- Implemented a pleasant pop sound (notification.mp3) that plays when a new unread notification arrives.

- Added a toggle in the User Profile page allowing users to enable/disable the sound.

services/dataService.ts

@@ -56,6 +56,32 @@ export const markAllNotificationsAsRead = async (): Promise<boolean> => {
   }
 };
 
+export const deleteNotification = async (id: string): Promise<boolean> => {
+  try {
+    const response = await fetch(`${API_URL}/notifications/${id}`, {
+      method: 'DELETE',
+      headers: getHeaders()
+    });
+    return response.ok;
+  } catch (error) {
+    console.error("API Error (deleteNotification):", error);
+    return false;
+  }
+};
+
+export const clearAllNotifications = async (): Promise<boolean> => {
+  try {
+    const response = await fetch(`${API_URL}/notifications`, {
+      method: 'DELETE',
+      headers: getHeaders()
+    });
+    return response.ok;
+  } catch (error) {
+    console.error("API Error (clearAllNotifications):", error);
+    return false;
+  }
+};
+
 export const searchGlobal = async (query: string): Promise<{ members: User[], teams: any[], attendances: any[], organizations?: any[] }> => {
   try {
     const response = await fetch(`${API_URL}/search?q=${encodeURIComponent(query)}`, {