- Add master_color as explicit SQL FILTER field in SearchItem (was in description)
- Add LIKE filter in _get_metadata_clauses for master_color + product_color_name
- Add MAX_BY(master_color) to final SELECT aggregation
- Fix color fallback in format_product_results (parse from description_text_full)
- Strengthen Rule 3a: specific design/pattern matching (con lợn, Disney, etc.)
- Add thảo mai exception: truthfulness > flattery when no products match
- Update tool prompt examples to use master_color as separate field