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/ralouphie/getallheaders/src/getallheaders.php

@@ -0,0 +1,46 @@
+<?php
+
+if (!function_exists('getallheaders')) {
+
+    /**
+     * Get all HTTP header key/values as an associative array for the current request.
+     *
+     * @return string[string] The HTTP header key/value pairs.
+     */
+    function getallheaders()
+    {
+        $headers = array();
+
+        $copy_server = array(
+            'CONTENT_TYPE'   => 'Content-Type',
+            'CONTENT_LENGTH' => 'Content-Length',
+            'CONTENT_MD5'    => 'Content-Md5',
+        );
+
+        foreach ($_SERVER as $key => $value) {
+            if (substr($key, 0, 5) === 'HTTP_') {
+                $key = substr($key, 5);
+                if (!isset($copy_server[$key]) || !isset($_SERVER[$key])) {
+                    $key = str_replace(' ', '-', ucwords(strtolower(str_replace('_', ' ', $key))));
+                    $headers[$key] = $value;
+                }
+            } elseif (isset($copy_server[$key])) {
+                $headers[$copy_server[$key]] = $value;
+            }
+        }
+
+        if (!isset($headers['Authorization'])) {
+            if (isset($_SERVER['REDIRECT_HTTP_AUTHORIZATION'])) {
+                $headers['Authorization'] = $_SERVER['REDIRECT_HTTP_AUTHORIZATION'];
+            } elseif (isset($_SERVER['PHP_AUTH_USER'])) {
+                $basic_pass = isset($_SERVER['PHP_AUTH_PW']) ? $_SERVER['PHP_AUTH_PW'] : '';
+                $headers['Authorization'] = 'Basic ' . base64_encode($_SERVER['PHP_AUTH_USER'] . ':' . $basic_pass);
+            } elseif (isset($_SERVER['PHP_AUTH_DIGEST'])) {
+                $headers['Authorization'] = $_SERVER['PHP_AUTH_DIGEST'];
+            }
+        }
+
+        return $headers;
+    }
+
+}