Update SiteController, use url validator in redirect endpoint

app/Http/Controllers/SiteController.php

@@ -9,6 +9,7 @@ use App\Util\Lexer\PrettyNumber;
 use App\{Follower, Page, Profile, Status, User, UserFilter};
 use App\Util\Localization\Localization;
 use App\Services\FollowerService;
+use App\Util\ActivityPub\Helpers;
 
 class SiteController extends Controller
 {
@@ -112,6 +113,7 @@ class SiteController extends Controller
             'url' => 'required|url'
         ]);
         $url = request()->input('url');
+        abort_if(Helpers::validateUrl($url) == false, 404);
         return view('site.redirect', compact('url'));
     }