feat(passport): stronger MRZ model + country-aware name extraction in the prompt
- PASSPORT_MODEL: google/gemini-3.5-flash-lite -> google/gemini-3.7-flash (better MRZ vision).
- PASSPORT_IMAGE_PROMPT now also asks for firstName/middleName/lastName with per-country naming rules (Iran/IRN: all given names -> firstName, middleName null; Arab IRQ/SAU/ARE/…: father/grandfather -> middleName; others: first word firstName, rest middleName).
Note: the parser (passport_image_logic.parse_mrz) still derives names from the MRZ l1/l2, so these new visual-zone name fields are not consumed yet — a follow-up is needed to prefer them.
Co-Authored-By: Claude Opus 4.8 (1M context) noreply@anthropic.com