fix: remove non-functional notification bell from header

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/src/components/Header.jsx

@@ -1,6 +1,6 @@
 import { useState, useRef, useEffect } from 'react'
 import { useLocation } from 'react-router-dom'
-import { Bell, ChevronDown, LogOut, Shield, Lock, AlertCircle, CheckCircle } from 'lucide-react'
+import { ChevronDown, LogOut, Shield, Lock, AlertCircle, CheckCircle } from 'lucide-react'
 import { useAuth } from '../contexts/AuthContext'
 import { getInitials, api } from '../utils/api'
 import Modal from './Modal'
@@ -103,12 +103,6 @@ export default function Header() {
         {/* Theme toggle */}
         <ThemeToggle />
 
-        {/* Notifications */}
-        <button className="relative p-2 rounded-lg hover:bg-surface-tertiary text-text-secondary hover:text-text-primary transition-colors">
-          <Bell className="w-5 h-5" />
-          <span className="absolute top-1.5 right-1.5 w-2 h-2 bg-red-500 rounded-full"></span>
-        </button>
-
         {/* User menu */}
         <div ref={dropdownRef} className="relative">
           <button