Fix: improve customer service selection flow and booking status

- Set new service bookings to PENDING instead of STARTED
- Show message when no services are available
- Add Select a Service header
- Add Enter Vehicle Details header
- Improve service selection screen flow

Fixes #1753

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

@@ -175,9 +175,16 @@ Return type: void
 void CustomerMenu::selectService()
 {
     std::string vehicleNumber, vehicleBrand, vehicleModel;
-	auto services = m_controller.getServices();
-    util::Vector<std::string> selectedServices;
     util::clear();
+    std::cout << "Select a Service\n";
+	auto services = m_controller.getServices();
+    if (services.isEmpty())
+    {
+        std::cout << "No services available!";
+        util::pressEnter();
+        return;
+    }
+    util::Vector<std::string> selectedServices;
     const Service* selectedService = selectServiceFromServices(services);
     if (selectedService == nullptr)
     {
@@ -187,6 +194,7 @@ void CustomerMenu::selectService()
     }
     selectedServices.push_back(selectedService->getId());
     util::clear();
+    std::cout << "Enter Vehicle Details\n";
     std::cout << "Enter vehicle number: ";
     util::read(vehicleNumber);
     std::cout << "Enter vehicle brand: ";