Fix AppConfigController: fallback to first academy for public endpoints

Single-academy deployments don't have current_academy bound for
unauthenticated API requests. Fall back to Academy::first() so
/api/v1/app/config works without auth.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Http/Controllers/Api/V1/AppConfigController.php

@@ -2,6 +2,7 @@
 
 namespace App\Http\Controllers\Api\V1;
 
+use App\Domain\Shared\Models\Academy;
 use App\Domain\Shared\Models\SystemSetting;
 use App\Http\Controllers\Controller;
 use Illuminate\Http\JsonResponse;
@@ -10,7 +11,11 @@ class AppConfigController extends Controller
 {
     public function index(): JsonResponse
     {
-        $academy = app('current_academy');
+        $academy = app()->bound('current_academy') ? app('current_academy') : null;
+
+        if (!$academy) {
+            $academy = Academy::first();
+        }
 
         if (!$academy) {
             return response()->json([