- Download GeoNames JP postal code database (142K entries)
- Create geocode_japan_postal.py with postal code lookup
- Handle unicode hyphen variants in postal codes
- Add manual mappings for remote Tokyo islands (Hachijojima, Miyakejima)
- Implement prefix fallback for company postal codes
- Total JP files geocoded: 540 (99.81% coverage)
This brings overall geocoding coverage from 97.84% to 99.81%