Immutable arbitrary-precision Money and Currency value objects for Laravel: ISO 4217 + custom currencies, exact decimal parsing, rounding-safe arithmetic and allocation, locale formatting, Eloquent casts and schema macros, validation, discounts, tax, and pluggable exchange rates (array, database, ECB).

Laravel Eloquent casts for PHP 8.4's BCMath\Number object API, enabling natural operator-based arithmetic on model attributes while maintaining arbitrary precision decimal accuracy.