Handle extended GND IDs (like 4114170-2 Fenster (Motiv))

Close #46

src/enums/MDNodaRepository.php

@@ -438,6 +438,11 @@ private static function validateGndId(string $id, array $prefixes):string|false
             $id = strtr($id, $toRemove);
         }
 
+        // Handle extended IDs (like "4114170-2 (Fenster (Motiv)")
+        if (str_contains($id, '(')) {
+            $id = trim(explode('(', $id)[0]);
+        }
+
         // There is an issue with this regex
         if (preg_match("/^[0-9-X]*$/", $id) === false) {
             return false;