Implement View Admin Notifications

<UserStory> NOT002: View Admin Notifications </UserStory>

<Changes>
    1. Added shared notification view handler `viewAndDeleteNotification()` in MenuHelper.h for notification viewing and deletion logic reuse.
    2. Updated AdminMenu.cpp to include MenuHelper.h and connected AdminMenu::viewNotifications() to the shared notification handler.
</Changes>

<Test>

    Precondition:
    1. Admin user exists and is logged into the system.
    2. Admin has one or more notifications available.
    3. “View Notifications” option is visible in the Admin menu.

    Steps:
    1. Navigate to Admin Menu.
    2. Select “View Notifications”.
    3. Verify that the system displays a list of notifications showing title, message, and timestamp.
    4. Select a notification to view full details.
       - Verify that the selected notification is displayed and deleted after viewing.
    5. Return to the notification list or reopen “View Notifications”.
       - Verify that the previously viewed notification is no longer present.

</Test>

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

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

@@ -1,6 +1,7 @@
 #include "AdminMenu.h"
 #include "InputHelper.h"
 #include "OutputHelper.h"
+#include "MenuHelper.h"
 
 void AdminMenu::showMenu()
 {
@@ -86,4 +87,5 @@ void AdminMenu::removeComboPackage()
 
 void AdminMenu::viewNotifications()
 {
+	viewAndDeleteNotification(m_controller);
 }

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

@@ -0,0 +1,6 @@
+#pragma once
+#include "Controller.h"
+
+inline void viewAndDeleteNotification(Controller& controller)
+{
+}