Updated the OrderService to utilize the new fromBasket method for creating orders, enhancing code clarity and maintainability. Removed the ProductAvailabilityService as its functionality is now integrated into the ProductRepository.
- Implement tests for product publication status.
- Add tests for product orderability based on various conditions.
- Enhance pricing calculation tests for different discount scenarios.
- Remove outdated PricingServiceTest and refactor ProductAvailabilityServiceTest.
