Add pytest and gitlab-ci for container

utils/config.py

@@ -54,7 +54,7 @@ class GalleryItem:
 class Config:
     """
     Main configuration class that aggregates all gallery settings.
-    
+
     Provides backward compatibility properties and methods for loading
     configuration from YAML files.
     """

utils/metadata.py

@@ -80,12 +80,12 @@ def get_metadata_file_path(folder_path: Path) -> str:
     """
     # Preferred order: YAML first, then JSON
     preferred_files = ['metadata.yaml', 'metadata.yml', 'metadata.json']
-        
+
     for filename in preferred_files:
         metadata_path = folder_path / filename
         if metadata_path.exists():
             return str(metadata_path)
-    
+
     # If no file exists, suggest metadata.yaml (preferred format)
     return str(folder_path / 'metadata.yaml')