Remove next-intl localization infrastructure

Strips out the i18n layer (next-intl, message files, language switcher,
provider) to reduce complexity. Nav components now use plain English strings.

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

src/components/layouts/applicant-nav.tsx

@@ -2,32 +2,30 @@
 
 import { Home, Users, FileText, MessageSquare } from 'lucide-react'
 import { RoleNav, type NavItem, type RoleNavUser } from '@/components/layouts/role-nav'
-import { useTranslations } from 'next-intl'
 
 interface ApplicantNavProps {
   user: RoleNavUser
 }
 
 export function ApplicantNav({ user }: ApplicantNavProps) {
-  const t = useTranslations('nav')
   const navigation: NavItem[] = [
     {
-      name: t('dashboard'),
+      name: 'Dashboard',
       href: '/applicant',
       icon: Home,
     },
     {
-      name: t('team'),
+      name: 'Team',
       href: '/applicant/team',
       icon: Users,
     },
     {
-      name: t('documents'),
+      name: 'Documents',
       href: '/applicant/documents',
       icon: FileText,
     },
     {
-      name: t('mentoring'),
+      name: 'Mentoring',
       href: '/applicant/mentor',
       icon: MessageSquare,
     },