Stand: SMTP-Test, Admin-Mail-Tab, Notifiable-Fix, Lazy-Quill

- Fix: Notifiable-Trait zum User-Model hinzugefuegt (behebt notify()-500er)
- Installer: SMTP-Verbindungstest mit EsmtpTransport + Ueberspringen-Link
- Admin: Neuer E-Mail-Tab mit SMTP-Konfiguration + Verbindungstest
- Admin: Lazy Quill-Initialisierung (nur sichtbare Locale wird geladen)
- Uebersetzungen: 17 neue Mail-Keys in allen 6 Sprachen

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

vendor/symfony/routing/Exception/MissingMandatoryParametersException.php

@@ -0,0 +1,49 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Routing\Exception;
+
+/**
+ * Exception thrown when a route cannot be generated because of missing
+ * mandatory parameters.
+ *
+ * @author Alexandre Salomé <alexandre.salome@gmail.com>
+ */
+class MissingMandatoryParametersException extends \InvalidArgumentException implements ExceptionInterface
+{
+    private string $routeName = '';
+    private array $missingParameters = [];
+
+    /**
+     * @param string[] $missingParameters
+     */
+    public function __construct(string $routeName = '', array $missingParameters = [], int $code = 0, ?\Throwable $previous = null)
+    {
+        $this->routeName = $routeName;
+        $this->missingParameters = $missingParameters;
+        $message = \sprintf('Some mandatory parameters are missing ("%s") to generate a URL for route "%s".', implode('", "', $missingParameters), $routeName);
+
+        parent::__construct($message, $code, $previous);
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getMissingParameters(): array
+    {
+        return $this->missingParameters;
+    }
+
+    public function getRouteName(): string
+    {
+        return $this->routeName;
+    }
+}