fix: normalize validation metadata required fields

Signed-off-by: Vitor Mattos <1079143+vitormattos@users.noreply.github.com>

Author: vitormattos

lib/Service/File/MetadataLoader.php

@@ -35,8 +35,6 @@ public function loadMetadata(?File $file, stdClass $fileData): void {
 			$fileNode = $this->getFileNode($file);
 			$metadata = $file->getMetadata() ?? [];
 
-			$fileData->metadata = $metadata;
-
 			if (method_exists($fileNode, 'getSize')) {
 				$fileData->size = $fileNode->getSize();
 			}
@@ -49,9 +47,15 @@ public function loadMetadata(?File $file, stdClass $fileData): void {
 			}
 
 			$fileData->pages = $this->getPages($file);
-
 			$fileData->totalPages = (int)($metadata['p'] ?? count($fileData->pages ?? []));
 			$fileData->pdfVersion = (string)($metadata['pdfVersion'] ?? '');
+
+			$metadata['p'] = $fileData->totalPages;
+			$extension = pathinfo($file->getName(), PATHINFO_EXTENSION);
+			if (!isset($metadata['extension']) || !is_string($metadata['extension']) || trim($metadata['extension']) === '') {
+				$metadata['extension'] = is_string($extension) && $extension !== '' ? strtolower($extension) : 'pdf';
+			}
+			$fileData->metadata = $metadata;
 		} catch (\Throwable $e) {
 			$this->logger->warning('Failed to load file metadata: ' . $e->getMessage());
 		}