feat: add api MFE configuration

[dcoa]

feat: add api MFE configuration

Description

This PR is a backport of all the commits related to MFE API configuration.

Supporting information

The related PR are:

• https://github.com/openedx/edx-platform/pull/30830
• https://github.com/openedx/edx-platform/pull/30473

Testing instructions

Please, follow the instructions here https://github.com/openedx/edx-platform/pull/30473

Additional information

JIRA CARD

[MaferMazu]

Hello Diana, thanks for this, but I wonder if we want this PR. The acceptance criteria for that Jira card are more about having a "productive" branch about CSS variables in the frontend platform and learning mfe and having a strain published around your work of CSS variables.

@santiagosuarezedunext @Alec4r, do you know if someone on the team uses MFE in Nutmeg and probably wants this?

The backport is okay, and these changes won't break things, but as I said, I am not so sure we want this because, as eduNEXT, we are trying these things in Olmo.

[dcoa]

@MaferMazu let me explain a little bit more the context:

1. Point 1 of the acceptance criteria talks about nuez and olmo releases.
2. The third acceptance criteria requests to describe how to have an environment with CSS variables, which is why we need this backport.

[dcoa]

Understanding that we are gonna use this in Olmo, I proceed to close this PR.

[dcoa]

It's all about configurations to enable the API you should have ENABLE_MFE_CONFIG_API in true and disable or enable MFE's with the django flags.

[JuanDavidBuitrago]

Thanks for the clarification @dcoa.