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/process/Exception/ProcessFailedException.php

@@ -0,0 +1,53 @@
+<?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\Process\Exception;
+
+use Symfony\Component\Process\Process;
+
+/**
+ * Exception for failed processes.
+ *
+ * @author Johannes M. Schmitt <schmittjoh@gmail.com>
+ */
+class ProcessFailedException extends RuntimeException
+{
+    public function __construct(
+        private Process $process,
+    ) {
+        if ($process->isSuccessful()) {
+            throw new InvalidArgumentException('Expected a failed process, but the given process was successful.');
+        }
+
+        $error = \sprintf('The command "%s" failed.'."\n\nExit Code: %s(%s)\n\nWorking directory: %s",
+            $process->getCommandLine(),
+            $process->getExitCode(),
+            $process->getExitCodeText(),
+            $process->getWorkingDirectory()
+        );
+
+        if (!$process->isOutputDisabled()) {
+            $error .= \sprintf("\n\nOutput:\n================\n%s\n\nError Output:\n================\n%s",
+                $process->getOutput(),
+                $process->getErrorOutput()
+            );
+        }
+
+        parent::__construct($error);
+
+        $this->process = $process;
+    }
+
+    public function getProcess(): Process
+    {
+        return $this->process;
+    }
+}