Item History Widget → New Column dialog allows clicking Add button without Item.

Steps to reproduce:

1. Open any dashboard.
2. Add a widget Item history or edit an existing one.
3. Go to Items -> Add.
4. In the popup, leave all fields empty (no item selected) or add Name only.
5. Press the Add button

Result:

Dialog closes, column is not added.

Expected:
If no Name/Item is selected, the user must see an error. Popup should not close if required fields are missing.