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>

api/app/Http/Requests/Api/V1/UpdateProfileRequest.php

@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Http\Requests\Api\V1;
+
+use Illuminate\Foundation\Http\FormRequest;
+
+final class UpdateProfileRequest extends FormRequest
+{
+    public function authorize(): bool
+    {
+        return true;
+    }
+
+    public function rules(): array
+    {
+        return [
+            'first_name' => ['required', 'string', 'max:100'],
+            'last_name' => ['required', 'string', 'max:100'],
+            'phone' => ['nullable', 'string', 'max:20'],
+            'date_of_birth' => ['nullable', 'date', 'before:today'],
+            'timezone' => ['required', 'string', 'timezone:all'],
+            'locale' => ['required', 'string', 'in:nl,en'],
+        ];
+    }
+}