Roles via Nextcloud groups: sms-admin/manager/viewer + fix OAuth instance_uri

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/Filament/User/Resources/ProductInventoryResource.php

@@ -2,6 +2,7 @@
 
 namespace App\Filament\User\Resources;
 
+use App\Traits\EnforcesRoles;
 use App\Filament\User\Resources\ProductInventoryResource\Pages;
 use Filament\Forms;
 use Filament\Forms\Form;
@@ -17,6 +18,7 @@ use Illuminate\Support\Facades\DB;
 
 class ProductInventoryResource extends Resource
 {
+    use EnforcesRoles;
     protected static ?string $model = ProductInventory::class;
 
     protected static ?string $navigationIcon = 'heroicon-o-inbox';