- Images step: folder drag-and-drop with recursive image scanning, per-file
list with format and size info, total file size in header, supported
formats label in empty state
- Compress step: per-format quality controls moved into AdwExpanderRow,
improved quality level descriptions
- Output step: dynamic image count with total size from loaded_files,
initial overwrite behavior from config
- Workflow step: properly handle MetadataConfig::Custom in preset import,
mapping all custom metadata fields to JobConfig