Add support for context-receivers

[DRSchlaubi]

This PR aims at implementing support for context receivers (#1232)

It currently only tries to implement a possible design for builders and specs and has no code generation logic

@OptIn(ContextReceivers::class)
public fun main() {
  val contextFunction = FunSpec.Builder("withContext")
    .contextReceiver(InputStream::class)
    .build()

  val contextLambda = LambdaTypeName.get(
    receiver = STRING,
    contextReceivers = listOf(InputStream::class.asTypeName()),
    returnType = STRING
  )
}

Fixes #1232

[ZacSweers]

Are you open to implementing the code gen part of it? I don't think it would be too difficult.

General design looks ok, left comments where there need to be changes.

In the future, please don't PR unrelated formatting changes that deviate from the code style we use, it makes the PR quite noisy.

[DRSchlaubi]

Are you open to implementing the code gen part of it? I don't think it would be too difficult.

I was going to propose an implementation with this design as well; however, I didn't I ran into an issue, which is why I just proposed a design, once that is finished I would be open to implement the code gen

In the future, please don't PR unrelated formatting changes that deviate from the code style we use, it makes the PR quite noisy.

I didn't mean to do that, looks like IntelliJ just ignored your .editorconfig

[DRSchlaubi]

I hope I caught all the code style violations?

[Egorand]

Sweet! Added a few comments, some of them (non-nit ones) would be nice to address before merging.

[Egorand]

@DRSchlaubi also please sign our CLA before we can merge you PR.

[DRSchlaubi]

Done

[Egorand]

Think it just needs a ./gradlew :kotlinpoet:spotlessApply.

[ZacSweers]

Can you confirm this is legal syntax?

[DRSchlaubi]

Using it in IntelliJ crashes intellij, however there is no real rules in the KEEP for how to use annotations and the compiler accepts it

[Egorand]

Merged, thank you!