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/phpunit/php-code-coverage/src/Report/Thresholds.php

@@ -0,0 +1,56 @@
+<?php declare(strict_types=1);
+/*
+ * This file is part of phpunit/php-code-coverage.
+ *
+ * (c) Sebastian Bergmann <sebastian@phpunit.de>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+namespace SebastianBergmann\CodeCoverage\Report;
+
+use SebastianBergmann\CodeCoverage\InvalidArgumentException;
+
+/**
+ * @immutable
+ */
+final class Thresholds
+{
+    private readonly int $lowUpperBound;
+    private readonly int $highLowerBound;
+
+    public static function default(): self
+    {
+        return new self(50, 90);
+    }
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    public static function from(int $lowUpperBound, int $highLowerBound): self
+    {
+        if ($lowUpperBound > $highLowerBound) {
+            throw new InvalidArgumentException(
+                '$lowUpperBound must not be larger than $highLowerBound',
+            );
+        }
+
+        return new self($lowUpperBound, $highLowerBound);
+    }
+
+    private function __construct(int $lowUpperBound, int $highLowerBound)
+    {
+        $this->lowUpperBound  = $lowUpperBound;
+        $this->highLowerBound = $highLowerBound;
+    }
+
+    public function lowUpperBound(): int
+    {
+        return $this->lowUpperBound;
+    }
+
+    public function highLowerBound(): int
+    {
+        return $this->highLowerBound;
+    }
+}