- Add serialize/deserialize support for core models
- Add file-based load/save functions in management services
- Introduce FileManager, Config, Utility and helper utilities
- Persist observer IDs for notification services
- Resolve object relationships during load (services, bookings, invoices, job cards)
- Add controller-level loadSystemData/saveSystemData
- Load data at app startup and save on shutdown
- Removed observer map from Subject base class
- Removed notify() from Subject interface
- Made NotificationManagementService abstract with pure virtual methods
- Added static observer maps to notification service implementations
- Added attach() and detach() overrides in inventory, payment, and service management services
- Added update() override in User model for observer pattern support
- Updated notification method declarations with override specifiers
<Changes>
1. Added State enum with ACTIVE and INACTIVE values in Enums.h.
2. Added state member, getter, and setter in User, Service, InventoryItem, and ComboPackage models.
3. Updated constructors to initialize model objects with ACTIVE state by default.
4. Added state string conversion helper functions in Enums.h.
5. Added default return values in Controller getter methods to complete stub implementations.
6. Added basic menu loop implementation in CustomerMenu and TechnicianMenu for handling user input.
</Changes>
Changes:
- Added stub implementations for Controller.cpp methods
- Fixed const issue in UserInterface methods (run, login, registerCustomer, handleOperation)
- Changed return types to use const pointers for read-only objects
- Updated maps and vectors to return const object pointers
- Fixed some function parameter names and signatures for consistency