[BUGFIX] Fix localization record merging logic.

Update the logic to correctly merge localized records by checking the presence of a '_LOCALIZED_UID' in the content object's data. This change ensures that records are only merged when a valid localized version is available.

I extracted $this->recoredService->getSingle(...) from the array_merge function because it had never merged the localised record on my system here.
Therefore, getSingle is saved in an extra variable and then merged if it exists.

Classes/Controller/AbstractFluxController.php

@@ -583,15 +583,18 @@ public function getRecord(): array
             );
         }
 
-        if ($record['_LOCALIZED_UID'] ?? false) {
-            $record = array_merge(
-                $record,
-                $this->recordService->getSingle(
-                    (string) $this->getFluxTableName(),
-                    '*',
-                    $record['_LOCALIZED_UID']
-                ) ?? $record
+        if ($contentObject->data['_LOCALIZED_UID'] ?? false) {
+            $localized = $this->recordService->getSingle(
+                (string) $this->getFluxTableName(),
+                '*',
+                $contentObject->data['_LOCALIZED_UID']
             );
+            if ($localized) {
+                $record = array_merge(
+                    $record,
+                    $localized
+                );
+            }
         }
         return $record;
     }