Manage access to allow devs to only work on a specific environment.

### Describe the feature you'd like to request

Lets say we have two environments, (prod and dev) and I want to give access to only dev environment to my team.
By default, in manage access section of amplify you can only give full access wich gives access to every environments...


But I want to restrict team permission to only be able to interact with the `env` environment

So far, only thread ive found about this were left with no answers.

### Describe the solution you'd like

1. Add an option to manage access on specific environnement

or

2. Provide a step by step guide on how to do it either in the doc or simply in this feature request discussion, so people can refer to this..

Thank you in advance.

### Describe alternatives you've considered

So far, only thread ive found about this were left with no answers.

I was thinking about creating a custom role for a specific environnment. Add required policies to the role then assign that role to users..

Start by reviewing the Amplify Studio Manage access flow described in the issue and the proposed custom IAM role and policies. Done means either team members can interact only with the specified environment, or a step-by-step guide explains how to configure those environment-scoped permissions.

Written by the indexing model from the issue text.