Ability to distinguish between the client and server component in turbopack loader

[AleksandrSl]

Goals

Be able to tell inside the loader that the code you're transforming is a client component. Currently client component goes through both condition: { not: "browser" } and condition: "browser", while server components go through condition: { not: "browser" } as expected.
The problem is that server part of the client component (Client Component SSR) still cannot use any of the server side APIs, but from the loader perspective there is no way to know that

Non-Goals

No response

Background

We are working on a library that modifies the code of the application for translation purposes and we need to inject different thing into the client and server components. So being able to tell client component from server is crucial

I saw this issue - #63150 - about conditions, but as I described in the goal client components fall under both "server" and "client" ones

Proposal

Since there is no metadata being passed to the loader, maybe there could be another condition? Something like "server-only" that will apply the loader only to the components that do not have the SSR part.