Client-Error-Endpoint POST /api/vitec/client-error (0072-FE / 0077-BE)

Neue PSR-15-Middleware ClientErrorMiddleware: nimmt Browser-Fehler des
React-Frontends als JSON {url, message, stack, release, userAgent}
entgegen und antwortet 204 ohne Body. Schutz: 30 Meldungen pro Minute
und IP (Sliding Window ueber TYPO3-RateLimiter, 429 + Retry-After),
8-KB-Body-Limit (413, Content-Length und tatsaechliche Bytes), kein
JSON-Objekt oder leere message = 400, GET = 405. Keine Session, keine
Cookies; der /_json-Praefix funktioniert ebenfalls.

Speicherung in der neuen Tabelle tx_vitec_clienterrorlog mit
anonymisierter IP (IPv4 letztes Oktett 0, IPv6 /48). Sichtbar als
Tabelle "Client errors (last 24 h)" im Modul VITEC SSR (mit Stack als
Aufklapper) und als Zeile "Client errors reported (24 h / 7 d)" in der
Dashboard-Kachel VITEC: SSR statistics.

CLI vitec:client-error-cleanup [--days=30] loescht Eintraege aelter als
30 Tage (taeglich per Cron).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

packages/vitec/Classes/Controller/Backend/SsrController.php

@@ -11,6 +11,7 @@ use TYPO3\CMS\Backend\Attribute\AsController;
 use TYPO3\CMS\Backend\Routing\UriBuilder;
 use TYPO3\CMS\Backend\Template\ModuleTemplateFactory;
 use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Database\Connection;
 use TYPO3\CMS\Core\Database\ConnectionPool;
 use TYPO3\CMS\Core\Http\JsonResponse;
 use TYPO3\CMS\Core\Http\RedirectResponse;
@@ -73,10 +74,51 @@ final class SsrController
             'healthError' => $healthError,
             'purgeLog' => $this->rows('tx_vitec_ssrpurgelog', 30),
             'healthLog' => $this->rows('tx_vitec_ssrhealthlog', 10),
+            'clientErrors' => $this->clientErrors(50),
+            'clientErrorCount24h' => $this->clientErrorCount24h(),
         ]);
         return $view->renderResponse('Ssr/Index');
     }
 
+    /**
+     * Client error reports of the last 24 hours (POST /api/vitec/client-error,
+     * ClientErrorMiddleware), newest first. Rows carry a "host" (URL without
+     * scheme/query) and a shortened user agent for the table; the full
+     * values stay in the row for the details toggle.
+     */
+    private function clientErrors(int $limit): array
+    {
+        try {
+            $qb = $this->connectionPool->getQueryBuilderForTable('tx_vitec_clienterrorlog');
+            $rows = $qb->select('*')->from('tx_vitec_clienterrorlog')
+                ->where($qb->expr()->gt('crdate', $qb->createNamedParameter(time() - 86400, Connection::PARAM_INT)))
+                ->orderBy('uid', 'DESC')->setMaxResults($limit)
+                ->executeQuery()->fetchAllAssociative();
+        } catch (\Throwable) {
+            return [];
+        }
+        foreach ($rows as &$row) {
+            $path = (string)(parse_url((string)$row['url'], PHP_URL_PATH) ?? '');
+            $row['path'] = $path !== '' ? $path : (string)$row['url'];
+            $ua = (string)$row['user_agent'];
+            $row['ua_short'] = mb_strlen($ua) > 60 ? mb_substr($ua, 0, 57) . '...' : $ua;
+            $row['is_chunk_reload'] = str_contains(strtolower((string)$row['message']), 'chunk reload');
+        }
+        unset($row);
+        return $rows;
+    }
+
+    private function clientErrorCount24h(): int
+    {
+        try {
+            return (int)$this->connectionPool->getConnectionForTable('tx_vitec_clienterrorlog')
+                ->executeQuery('SELECT COUNT(*) FROM tx_vitec_clienterrorlog WHERE crdate > ?', [time() - 86400])
+                ->fetchOne();
+        } catch (\Throwable) {
+            return 0;
+        }
+    }
+
     public function purgeAction(ServerRequestInterface $request): ResponseInterface
     {
         $body = (array)$request->getParsedBody();