feat: add "Lid toevoegen als deelnemer" shortcut for org members

Adds two new API endpoints to quickly add organisation members as event
persons with user_id pre-linked and status approved:
- GET /organisations/{org}/members/available-for-event/{event}
- POST /organisations/{org}/events/{event}/persons/from-member

Includes frontend dialog with member search, crowd type selection, and
click-to-add behavior in the Personen tab.

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

api/app/Http/Controllers/Api/V1/MemberController.php

@@ -8,7 +8,9 @@ use App\Http\Controllers\Controller;
 use App\Http\Requests\Api\V1\UpdateMemberRequest;
 use App\Http\Resources\Api\V1\MemberCollection;
 use App\Http\Resources\Api\V1\MemberResource;
+use App\Models\Event;
 use App\Models\Organisation;
+use App\Models\Person;
 use App\Models\User;
 use App\Services\EmailChangeService;
 use Illuminate\Http\JsonResponse;
@@ -84,6 +86,35 @@ final class MemberController extends Controller
         return response()->json(null, 204);
     }
 
+    public function availableForEvent(Organisation $organisation, Event $event): JsonResponse
+    {
+        if ($event->organisation_id !== $organisation->id) {
+            abort(404);
+        }
+
+        Gate::authorize('viewAny', [Person::class, $event]);
+
+        $existingUserIds = Person::withoutGlobalScopes()
+            ->where('event_id', $event->id)
+            ->whereNotNull('user_id')
+            ->pluck('user_id');
+
+        $members = $organisation->users()
+            ->whereNotIn('users.id', $existingUserIds)
+            ->select('users.id', 'users.first_name', 'users.last_name', 'users.email')
+            ->orderBy('users.first_name')
+            ->get()
+            ->map(fn (User $user) => [
+                'id' => $user->id,
+                'first_name' => $user->first_name,
+                'last_name' => $user->last_name,
+                'full_name' => $user->full_name,
+                'email' => $user->email,
+            ]);
+
+        return response()->json(['data' => $members]);
+    }
+
     /**
      * POST /api/v1/organisations/{organisation}/members/{user}/change-email
      * Admin changes a member's email (sends verification to new address).