List all 178 countries covered by the GlobalRules country-facts API, returned as ISO 3166-1 alpha-2 codes with country names. Use this endpoint first to discover which countries you can query for practical travel and business facts such as VAT rates, public holidays, tipping customs, power plugs, emergency numbers and visa rules (57 topics per country). Designed for AI agents, travel planners and cross-border e-commerce tools.