[KSP2] Kotlin Function* types reports inconsistent package and qualified names

[ZacSweers]

Given a function signature like so

fun example(input: Function0<String>) {

}

In KSP2, the Function0 type here reports the following information in its KSClassDeclaration:

• packageName resolves to kotlin.jvm.functions
• qualifiedName resolves to kotlin.Function0
• simpleName resolves to Function0

(typeOf<Function0<*>>().classifier as KClass<*>).qualifiedName reports kotlin.Function0, but the declaration is defined in the stdlib at kotlin.jvm.functions.Function0.

I'm not sure what the right answer is for this, but more importantly it's also unclear what a code generator (such as KotlinPoet) should use when mapping the type to something like a KotlinPoet TypeName representation.