feat: account settings with Vuexy tab pattern and MFA banner fix

Restructures account/profile pages to match Vuexy's account-settings
tab pattern (Account, Security, Notifications) and fixes the MFA
enforcement banner that stayed visible after successful setup.

Backend:
- Add phone column to users table with migration
- Add PUT /me/profile endpoint for profile updates
- Create UpdateProfileRequest form request
- Update MeResource to include phone field

Organizer app:
- Rewrite account-settings as tabbed page (VTabs pill style + VWindow)
- Create AccountTab: avatar, profile form, email change, danger zone
- Create SecurityTab: password change, MFA method cards, backup codes,
  trusted devices, disable MFA danger zone
- Create NotificationsTab: placeholder with disabled toggles
- Fix MFA banner: set authStore.mfaSetupRequired = false on setup complete
- Update router guard to redirect to ?tab=security for MFA enforcement
- Update UserProfile menu links to use tab query params

Portal:
- Restructure profiel.vue with VTabs (Mijn profiel + Beveiliging)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/app/src/plugins/1.router/guards.ts

@@ -45,9 +45,9 @@ export function setupGuards(router: Router) {
     }
 
     // MFA enforcement — redirect to security settings if MFA setup is required
-    if (authStore.mfaSetupRequired && to.path !== '/account-settings/security') {
+    if (authStore.mfaSetupRequired && to.path !== '/account-settings') {
       if (import.meta.env.DEV) console.log('🔒 MFA setup required, redirecting to security settings')
-      return { path: '/account-settings/security' }
+      return { path: '/account-settings', query: { tab: 'security' } }
     }
 
     // Platform admin routes — require super_admin role