data/
  master_countries.sql       # 281 canonical entities
  countries.sql              # 9,536 country-year records
  categories.sql             # 83,682 category records
  field_name_mappings.sql    # 1,132 field name standardization rules
  fields/
    country_fields_1990.sql.gz  # Split by year (36 gzipped files)
    ...
    country_fields_2025.sql.gz
schema/
  create_tables.sql          # DDL for all 5 tables
  create_field_values.sql    # DDL for FieldValues (structured sub-values)
etl/
  build_archive.py           # HTML parser (2000-2020)
  load_gutenberg_years.py    # Text parser (1990-2001)
  reload_json_years.py       # JSON loader (2021-2025)
  build_field_mappings.py    # Field name standardization
  classify_entities.py       # Entity type classification
  repair_1996_truncated.py   # CIA original text parser for 7 truncated 1996 countries
  validate_integrity.py      # Data quality checks
  export_to_sqlite.py        # SQL Server -> SQLite export (with FTS5)
  structured_parsing/
    parse_field_values.py    # Decompose text blobs into typed sub-values (55 parsers)
    validate_field_values.py # Validation: spot checks, coverage, numeric stats
    export_field_value