feat: crowd lists audit, enum, factory, service and tests

Audit and complete the Crowd Lists module:
- Add CrowdListType enum (internal/external) with proper casts
- Create CrowdListService for business logic (add/remove person,
  max_persons enforcement, auto_approve, activity logging)
- Create CrowdListFactory with Dutch names and states
- Create AddPersonToCrowdListRequest form request
- Fix FormRequests to use Rule::enum instead of hardcoded strings
- Fix CrowdListResource to use enum->value and add is_full field
- Refactor controller to be thin (delegates to service)
- Add eager loading for crowdType and recipientCompany
- Write 18 comprehensive tests (CRUD, auth, edge cases)
- Update API.md with request/response documentation

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

api/database/factories/CrowdListFactory.php

@@ -0,0 +1,74 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Database\Factories;
+
+use App\Enums\CrowdListType;
+use App\Models\Company;
+use App\Models\CrowdList;
+use App\Models\CrowdType;
+use App\Models\Event;
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/** @extends Factory<CrowdList> */
+final class CrowdListFactory extends Factory
+{
+    private const INTERNAL_NAMES = [
+        'VIP Gastenlijst',
+        'Backstage Crew',
+        'Barpersoneel',
+        'Opbouw Team',
+        'Afbouw Team',
+        'Vrijwilligers Hoofdpodium',
+        'Nachtploeg',
+        'EHBO Team',
+        'Parkeerteam',
+        'Kassa Medewerkers',
+    ];
+
+    private const EXTERNAL_NAMES = [
+        'Catering Medewerkers',
+        'Beveiligingspersoneel',
+        'Technische Crew',
+        'Schoonmaakploeg',
+        'Leveranciers Personeel',
+    ];
+
+    /** @return array<string, mixed> */
+    public function definition(): array
+    {
+        return [
+            'event_id' => Event::factory(),
+            'crowd_type_id' => CrowdType::factory(),
+            'name' => fake()->randomElement(self::INTERNAL_NAMES),
+            'type' => CrowdListType::INTERNAL,
+            'recipient_company_id' => null,
+            'auto_approve' => false,
+            'max_persons' => null,
+        ];
+    }
+
+    public function external(): static
+    {
+        return $this->state(fn () => [
+            'name' => fake()->randomElement(self::EXTERNAL_NAMES),
+            'type' => CrowdListType::EXTERNAL,
+            'recipient_company_id' => Company::factory(),
+        ]);
+    }
+
+    public function withAutoApprove(): static
+    {
+        return $this->state(fn () => [
+            'auto_approve' => true,
+        ]);
+    }
+
+    public function withMaxPersons(int $max): static
+    {
+        return $this->state(fn () => [
+            'max_persons' => $max,
+        ]);
+    }
+}