[klib] Add an option to write out header klibs

The header klib is supposed to only contain the public abi of the module
similar to jvm-abi-gen. It is intended to be used as a dependency for other
klib compilations instead of the full klib for compilation avoidance.

^KT-60807

native/native.tests/testData/klib/header-klibs/comparison/classPrivateMembers/base/A.kt

@@ -0,0 +1,18 @@
+package test
+
+class A {
+    val publicVal = 0
+    fun publicMethod() = 0
+
+    internal val internalVal = 0
+    internal fun internalMethod() = 0
+
+    protected val protectedVal = 0
+    protected fun protectedMethod() = 0
+
+    private val privateVal = 0
+    private fun privateMethod() = 0
+
+    val publicValBody = internalMethod() + privateMethod() + 2
+    val publicMethodBody = publicValBody + 2
+}