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/var-dumper/Dumper/ContextualizedDumper.php

@@ -0,0 +1,40 @@
+<?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\VarDumper\Dumper;
+
+use Symfony\Component\VarDumper\Cloner\Data;
+use Symfony\Component\VarDumper\Dumper\ContextProvider\ContextProviderInterface;
+
+/**
+ * @author Kévin Thérage <therage.kevin@gmail.com>
+ */
+class ContextualizedDumper implements DataDumperInterface
+{
+    /**
+     * @param ContextProviderInterface[] $contextProviders
+     */
+    public function __construct(
+        private DataDumperInterface $wrappedDumper,
+        private array $contextProviders,
+    ) {
+    }
+
+    public function dump(Data $data): ?string
+    {
+        $context = $data->getContext();
+        foreach ($this->contextProviders as $contextProvider) {
+            $context[$contextProvider::class] = $contextProvider->getContext();
+        }
+
+        return $this->wrappedDumper->dump($data->withContext($context));
+    }
+}