Enatega Admin Dashboard: Categories for products keep getting added with the same name, there should be only one entry for one name.

Describe the bug
The system currently allows multiple product categories to be created with the same name. This results in duplicate entries for identical category names, leading to confusion in both the admin panel and the app UI. There should be a validation to ensure that only one category with a given name can exist.

Steps to Reproduce:

Go to the Admin panel.
Add a new product category (e.g., "Burgers").
Attempt to add another category with the same name ("Burgers").
Observe that the system allows it without any warning or error.
Expected behavior
System should prevent adding duplicate category names by showing a validation message like “Category with this name already exists.”

Desktop (please complete the following information):

OS: [e.g. Windows]
Browser [e.g. Chrome]
Version [e.g. Latest]

Start in the Admin panel's product-category creation flow and trace how a category name is checked before it is saved. Reproduce the duplicate “Burgers” case, then verify that a second category with the same name is rejected with a validation message and that existing category creation still works.

Written by the indexing model from the issue text.