list_eu_vat_rates and get_country_vat_rates now return `identifiers`: the
names of the company registrar, the register, the register number, the
tax ID and the VAT ID, keyed by language (every official language plus
"en") or null, the same block /v1/rates returns. eu-vat-rates-data is
bumped to 2026.9.29, which carries them.