feat: implemented script for processing location data
Implemented a stream-based cities data processing pipeline using stream-json Added logic for:
- streaming read of large raw cities dataset
- region resolution using polygon lookup (script uses the which-polygon library together with the regions.geojson dataset to determine the region for each city based on its geographic coordinates)
- city name normalization
- country name enrichment based on iso country codes (script enriches each city record with a normalized English country name using the i18n-iso-countries library)
- filtering invalid records without matched regions
- streaming write of processed output