Load custom babel/swc plugins

[itsyoboieltr]

Goals

1. I would like to use lingui to implement email i18n.
2. lingui uses macros (transpilation) to hide the complexity of i18n management from the developers, which is great, but this causes react-email to fail.
3. It would be great if I could add the babel or swc plugin to the react email app somehow, allowing translations to be transpiled correctly.

Background

That's all.

Proposal

No idea. I need to look into the codebase.