Filtering users by their roles in a custom relation field

Hi, I have 2 collections:

  • User (default)
  • Contracts: title, description, customer, employee

The customer and employee are relation fields pointing to the User collection.
In the settings, I created 2 roles: customer and employee.

I aim to create a custom select field that takes an attribute (say called customer) and filters all users with the role of customer.

How would I do that? I tried other ways that work, but I believe they are bad practices. One of those “bad practices” would be just to add 2 collections (customer and employee) and relate them to the user collection, this will duplicate the data and would not give me the result I am looking for in the long term after expansion.

I believe my way is to code a custom component. If you guys see it solveable in a different way please let me know. I am new to strapi and would not prefer to mess with code.