SSR control center: English UI strings throughout

Widgets, backend module template and flash messages now match the rest of the backend, which is English.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

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

@@ -88,12 +88,12 @@ final class SsrController
         }
 
         if ($paths === []) {
-            $this->flash('Keine Pfade angegeben.', 'Purge', false);
+            $this->flash('No paths given.', 'Purge', false);
         } else {
             $result = $this->purgeService->purge($paths, 'module:' . $user);
             $this->flash(
                 sprintf('HTTP %d — %s', $result['httpCode'], $result['message']),
-                $result['success'] ? 'Purge erfolgreich' : 'Purge fehlgeschlagen',
+                $result['success'] ? 'Purge successful' : 'Purge failed',
                 $result['success']
             );
         }