fix: cleanup and small improvements

- added empty check in inventory alerts
- corrected parts cost calculation
- removed unused getUser method
- updated default admin password
- fixed missing includes in menus
- cleaned up MenuHelper comments

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/views/AdminMenu.cpp

@@ -10,6 +10,7 @@ Date: 19-May-2026
 
 #include <iomanip>
 #include <iostream>
+#include "AdminMenu.h"
 #include "Enums.h"
 #include "InputHelper.h"
 #include "InventoryItem.h"

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/views/CustomerMenu.cpp

@@ -10,8 +10,10 @@ Date:19-May-2026
 #include <iomanip>
 #include "ComboPackage.h"
 #include "CustomerMenu.h"
+#include "MenuHelper.h"
 #include "Enums.h"
 #include "InputHelper.h"
+#include "OutputHelper.h"
 #include "InventoryItem.h"
 #include "Invoice.h"
 #include "Map.h"

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/views/MenuHelper.h

@@ -29,9 +29,8 @@ Date: 21-May-2026
 #include "Validator.h"
 #include "Vector.h"
 
-
 /*
-Function: selectServicesToRemove (static helper)
+Function: selectServicesToRemove
 Description: Allows selection of a service to remove by index.
 Parameters:
     - currentServices: util::Map<std::string, const Service*>, available services
@@ -84,7 +83,7 @@ inline std::string selectServicesToRemove(util::Map<std::string, const Service*>
 }
 
 /*
-Function: selectInventoryItems (static helper)
+Function: selectInventoryItems 
 Description: Allows selection of inventory items by index for creating a service.
 Parameters:
 	- currentInventoryItems: util::Map<std::string, const InventoryItem*>&, available inventory items
@@ -158,7 +157,7 @@ static void selectInventoryItems(util::Map<std::string, const InventoryItem*>& c
 }
 
 /*
-Function: listServiceBookings (static helper)
+Function: listServiceBookings  
 Description: Lists all pending service bookings and maps them to indices for selection.
 Parameters:
 	- currentBookings: util::Map<std::string, const ServiceBooking*>&, current bookings
@@ -214,7 +213,7 @@ static bool listServiceBookings(util::Map<std::string, const ServiceBooking*>& c
 }
 
 /*
-Function: selectPendingServiceBookings (static helper)
+Function: selectPendingServiceBookings  
 Description: Allows selection of a pending service booking by index.
 Parameters:
 	- serviceBookingsMap: util::Map<int, const ServiceBooking*>&, map of indexed bookings
@@ -238,7 +237,7 @@ static const ServiceBooking* selectPendingServiceBookings(util::Map<int, const S
 }
 
 /*
-Function: listAvailableTechnicians (static helper)
+Function: listAvailableTechnicians 
 Description: Lists all available technicians and maps them to indices for selection.
 Parameters:
 	- currentAvailableTechnicians: util::Map<std::string, const User*>, available technicians
@@ -278,7 +277,7 @@ static void listAvailableTechnicians(util::Map<std::string, const User*> current
 }
 
 /*
-Function: selectTechnician (static helper)
+Function: selectTechnician 
 Description: Allows selection of a technician by index.
 Parameters:
 	- currentAvailableTechniciansMap: util::Map<int, const User*>&, map of indexed technicians
@@ -301,7 +300,7 @@ static const User* selectTechnician(util::Map<int, const User*>& currentAvailabl
 }
 
 /*
-Function: selectInvoiceFromUserForPayment (static helper)
+Function: selectInvoiceFromUserForPayment 
 Description: Lists all pending invoices for the customer and allows selection by index.
 Parameters:
 	- currentInvoices: util::Map<std::string, const Invoice*>&, map of customer invoices
@@ -366,7 +365,7 @@ static std::string selectInvoiceFromUserForPayment(const util::Map<std::string,
 }
 
 /*
-Function: selectPaymentMode (static helper)
+Function: selectPaymentMode 
 Description: Allows the customer to select a payment mode (ONLINE or OFFLINE).
 Parameters:
 	- None
@@ -396,7 +395,7 @@ static util::PaymentMode selectPaymentMode()
 }
 
 /*
-Function: displayInvoices (static helper)
+Function: displayInvoices 
 Description: Displays detailed information for all invoices associated with the customer,
 			 including booking details, technician, discount, total amount, payment status, and items used.
 Parameters:
@@ -464,7 +463,7 @@ static void displayInvoices(util::Map<std::string, const Invoice*> currentUserIn
 }
 
 /*
-Function: selectJobCardToComplete (static helper)
+Function: selectJobCardToComplete 
 Description: Lists all incomplete job cards assigned to the technician and allows selection by index.
 Parameters:
 	- assignedJobCards: util::Map<std::string, const JobCard*>&, job cards assigned to the technician
@@ -801,18 +800,7 @@ inline const ComboPackage* selectComboPackageFromPackages(const util::Map<std::s
 }
 
 /*
-Function: sendLowStockAlertsToAdmins (static helper)
-Description: Sends low stock alert notifications to all admin users for a given inventory item.
-Parameters:
-    - inventoryManagementService: InventoryManagementService&, service used to send notifications
-    - inventoryItem: const InventoryItem*, pointer to the low-stock inventory item
-    - adminUsers: const util::Vector<User*>&, list of admin users to notify
-Returns:
-    - None
-*/
-
-/*
-Function: getNotificationPreference (static helper)
+Function: getNotificationPreference 
 Description: Helper function to configure notification preferences for a specific service.
 Parameters:
     - serviceName: Name of the service for which notifications are being configured.