Implement Remove Stock Functionality

<UserStory> INV003: Remove Stock </UserStory>

<Changes>
    1. Integrated InventoryManagementService into Controller to handle removal of inventory items.
    2. Implemented InventoryManagementService::removeInventoryItem to mark items as INACTIVE in the datastore.
    3. Enhanced AdminMenu with removeInventoryItem workflow:
       - Displays inventory list with index, ID, part name, quantity, and price.
       - Allows admin to select item by index for removal.
       - Provides confirmation message after successful deletion.
    4. Added static helper function displayInventoryWithItems in AdminMenu for modularized inventory display.
</Changes>

<Test>

  Precondition:
  1. Admin user is logged into the system.
  2. Inventory contains multiple items with unique IDs.
  3. DataStore is initialized and accessible.

  Steps:
  1. Navigate to Admin Menu and select "Remove Inventory Item".
    - Verify that the system displays all inventory items with ID, part name, quantity, and price.
  2. Select an item by entering its index.
    - Verify that the system removes the item and displays a confirmation message.
  3. Attempt to remove an item with an invalid index.
    - Verify that the system rejects the input and shows an error message.
  4. Navigate to "View Stock Levels".
    - Verify that the removed item no longer appears in the inventory list.
</Test>

<Review>
Sreeja Reghukumar
</Review>

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/services/InventoryManagementService.cpp

@@ -1 +1,15 @@
 #include "InventoryManagementService.h"
+#include "InventoryItem.h"
+
+void InventoryManagementService::removeInventoryItem(const std::string& inventoryItemID)
+{
+    int index = m_dataStore.getInventoryItems().find(inventoryItemID);
+    if (index != -1)
+    {
+        InventoryItem* item = m_dataStore.getInventoryItems().getValueAt(index);
+        if (item != nullptr)
+        {
+            item->setState(util::State::INACTIVE);
+        }
+    }
+}