feat(notifications): implement notification system with CRUD operations and UI integration

src/components/Navbar.jsx

@@ -4,6 +4,7 @@ import { useLanguage } from '../contexts/LanguageContext';
 import { useNavigate } from 'react-router-dom';
 import { useState, useRef, useEffect } from 'react';
 import api from '../services/api';
+import NotificationBell from './NotificationBell';
 
 export default function Navbar({ onMenuClick }) {
   const { user, logout } = useAuth();
@@ -51,6 +52,9 @@ export default function Navbar({ onMenuClick }) {
 
         {/* Right section */}
         <div className="flex items-center gap-2">
+          {/* Notification bell */}
+          <NotificationBell />
+
           {/* User dropdown */}
           <div className="relative" ref={dropdownRef}>
             <button