Version 0.1.7 release

Highlights

• open-data-products generate --kind=product --input <source_docs/> now
  processes each .md and .txt source document separately with the selected
  product prompt.
• Folder input now runs one selected-kind generation attempt per source file, so
  a folder of product source documents produces matching
  product_reference_*.yaml fragments in the output folder.
• open-data-products generate now requires an explicit concrete --kind
  value; the old full-set generation mode has been removed from the CLI.
• The public Python API now exposes generate_local_artifacts_for_kind() for
  selected-kind multi-source generation.