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/league/flysystem/src/UnableToRetrieveMetadata.php

@@ -0,0 +1,76 @@
+<?php
+
+declare(strict_types=1);
+
+namespace League\Flysystem;
+
+use RuntimeException;
+use Throwable;
+
+final class UnableToRetrieveMetadata extends RuntimeException implements FilesystemOperationFailed
+{
+    /**
+     * @var string
+     */
+    private $location;
+
+    /**
+     * @var string
+     */
+    private $metadataType;
+
+    /**
+     * @var string
+     */
+    private $reason;
+
+    public static function lastModified(string $location, string $reason = '', ?Throwable $previous = null): self
+    {
+        return static::create($location, FileAttributes::ATTRIBUTE_LAST_MODIFIED, $reason, $previous);
+    }
+
+    public static function visibility(string $location, string $reason = '', ?Throwable $previous = null): self
+    {
+        return static::create($location, FileAttributes::ATTRIBUTE_VISIBILITY, $reason, $previous);
+    }
+
+    public static function fileSize(string $location, string $reason = '', ?Throwable $previous = null): self
+    {
+        return static::create($location, FileAttributes::ATTRIBUTE_FILE_SIZE, $reason, $previous);
+    }
+
+    public static function mimeType(string $location, string $reason = '', ?Throwable $previous = null): self
+    {
+        return static::create($location, FileAttributes::ATTRIBUTE_MIME_TYPE, $reason, $previous);
+    }
+
+    public static function create(string $location, string $type, string $reason = '', ?Throwable $previous = null): self
+    {
+        $e = new static("Unable to retrieve the $type for file at location: $location. {$reason}", 0, $previous);
+        $e->reason = $reason;
+        $e->location = $location;
+        $e->metadataType = $type;
+
+        return $e;
+    }
+
+    public function reason(): string
+    {
+        return $this->reason;
+    }
+
+    public function location(): string
+    {
+        return $this->location;
+    }
+
+    public function metadataType(): string
+    {
+        return $this->metadataType;
+    }
+
+    public function operation(): string
+    {
+        return FilesystemOperationFailed::OPERATION_RETRIEVE_METADATA;
+    }
+}