Implement Complete Payments

<UserStory> PAY002: Complete Payments </UserStory>

<Changes>
    1. Integrated Controller with PaymentManagementService to support payment completion workflow.
    2. Implemented PaymentManagementService::completePayment with validation for invoice ID, payment mode, and status update.
    3. Enhanced CustomerMenu with helper functions to display pending invoices in tabular format and allow index-based selection.
    4. Added CustomerMenu::selectPaymentMode to capture payment mode choice (OFFLINE/ONLINE).
    5. Updated CustomerMenu::completePayments to handle invoice selection, payment mode input, and trigger payment completion via Controller.
    6. Implemented notification logic to send confirmation to customers upon successful payment.
</Changes>

<Test>

 Acceptance Criteria:
 1. Payment status marked completed.
 2. Confirmation message shown.
 3. Confirmation notification sent.

 Precondition:
  1. Customer is logged into the system.
  2. At least one pending invoice exists for the customer.
  3. Datastore is available for storing invoices and updating payment status.

 Steps:
  1. Navigate to Customer menu and choose "Complete Payments".
    - Verify that the system lists pending invoices with tabular details.
  2. Select an invoice by index.
    - Verify that the chosen invoice is retrieved correctly.
  3. Enter payment mode (OFFLINE/ONLINE).
    - Verify that the selected mode is applied to the invoice.
  4. Confirm payment completion.
    - Verify that the invoice status changes to COMPLETED.
    - Verify that a confirmation message is displayed.
    - Verify that a notification is sent to the customer.
</Test>

<Review>
Sreeja Reghukumar, please review
</Review>

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

@@ -1,6 +1,13 @@
+#include <iomanip>
+#include <iostream>
 #include "CustomerMenu.h"
 #include "InputHelper.h"
 #include "OutputHelper.h"
+#include "Invoice.h"
+#include "Enums.h"
+#include "ServiceBooking.h"
+#include "User.h"
+#include "Timestamp.h"
 
 void CustomerMenu::showMenu()
 {
@@ -55,8 +62,96 @@ void CustomerMenu::viewServiceHistory()
 {
 }
 
+static std::string selectInvoiceFromUserForPayment(const util::Map<std::string, const Invoice*>& currentInvoices)
+{
+    int currentIndex = 1, choice;
+    util::Map<int, const Invoice*> pendingInvoicesForPayment;
+    std::cout << std::left
+        << std::setw(6) << "Index"
+        << std::setw(12) << "BookingID"
+        << std::setw(15) << "VehicleBrand"
+        << std::setw(15) << "VehicleNumber"
+        << std::setw(12) << "TechID"
+        << std::setw(20) << "TechnicianName"
+        << std::setw(10) << "Discount(%)"
+        << std::setw(12) << "TotalAmount"
+        << std::setw(20) << "InvoiceDate"
+        << std::endl;
+    for (int iterator = 0; iterator < currentInvoices.getSize(); iterator++)
+    {
+        const Invoice* currentInvoice = currentInvoices.getValueAt(iterator);
+        if (currentInvoice && currentInvoice->getStatus() == util::PaymentStatus::PENDING)
+        {
+            std::cout << std::left
+                << std::setw(6) << currentIndex
+                << std::setw(12) << currentInvoice->getBookingId()
+                << std::setw(15) << currentInvoice->getBooking()->getVehicleBrand()
+                << std::setw(15) << currentInvoice->getBooking()->getVehicleNumber()
+                << std::setw(12) << currentInvoice->getBooking()->getAssignedTechnician()->getId()
+                << std::setw(20) << currentInvoice->getBooking()->getAssignedTechnician()->getName()
+                << std::setw(10) << currentInvoice->getDiscountPercentage()
+                << std::setw(12) << currentInvoice->getTotalAmount()
+                << std::setw(20) << currentInvoice->getInvoiceDate().toString()
+                << std::endl;
+            pendingInvoicesForPayment.insert(currentIndex++, currentInvoice);
+        }
+    }
+    if (pendingInvoicesForPayment.getSize() == 0)
+    {
+        std::cout << "No pending invoices available for payment.\n";
+        return "";
+    }
+    std::cout << "Select the Invoice to pay (Index): ";
+    util::read(choice);
+    int selectedIndex = pendingInvoicesForPayment.find(choice);
+    if (selectedIndex != -1)
+    {
+        const Invoice* selectedInvoice = pendingInvoicesForPayment.getValueAt(selectedIndex);
+        return selectedInvoice->getId();
+    }
+    else
+    {
+        std::cout << "Invalid choice.\n";
+        return "";
+    }
+}
+
+static util::PaymentMode selectPaymentMode()
+{
+    int choice;
+    std::cout << "Enter the payment Mode\n1.OFFLINE\n2.ONLINE\nChoice: ";
+    util::read(choice);
+    if (choice == 1)
+    {
+        std::cout << "Offline mode selected.\n";
+        return util::PaymentMode::OFFLINE;
+    }
+    else if (choice == 2)
+    {
+        std::cout << "Online mode selected.\n";
+        return util::PaymentMode::ONLINE;
+    }
+    else
+    {
+        std::cout << "Invalid choice, Offline mode selected.\n";
+        return util::PaymentMode::OFFLINE;
+    }
+}
+
 void CustomerMenu::completePayments()
 {
+	util::clear();
+    int paymentModeChoice;
+	util::Map<std::string, const Invoice*> currentInvoices = m_controller.getInvoicesByUser();
+	std::string selectedID = selectInvoiceFromUserForPayment(currentInvoices);
+    if (selectedID == "")
+    {
+        std::cout << "Payment failed.\n";
+        return;
+    }
+    util::PaymentMode paymentMode = selectPaymentMode();
+    m_controller.completePayment(selectedID, paymentMode);
+    std::cout << "Payment completed successfully.\n";
 }
 
 void CustomerMenu::viewInvoices()