Folder-only mode (-N suffix files) was sending minimal metadata that DAM
rejected with "unmarshalling parameter" error. Now uses a reference
asset_representation_template.json as the base for all metadata fields,
ensuring the full field structure (column_name, data_type, domain_id, etc.)
the DAM API requires. Also fixes default/forced value handling to use
DomainValue format for domained fields from the template.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
