Introduce hands-on exercises with tests covering:
* part1: MoneyExercises, ArithmeticExercises, RoundingExercises,
FormattingExercises, ParsingExercises, IntegrationExercises
* part2: CurrencyConversionExercises, MonetaryOperatorExercises,
MonetaryQueryExercises, MonetaryContextExercises,
RoundingStrategyExercises
* part3: OrderExercises (end-to-end order workflow)
Use incomplete production methods with TODOs and complete JUnit 5 tests
(AssertJ only). Tests focus on observable behavior and avoid fragile
assertions (e.g., no fixed FX rates). Ensure clear progression from
basics to advanced concepts and final integration task.
Marcus Fihlon
21d835b9ca
