K2: Support callable references adaptation on top-level

^KT-45989 In progress
^KT-54709 Related
^KT-55217 Fixed

compiler/testData/diagnostics/tests/callableReference/adapted/simpleAdaptationOutsideOfCall.fir.kt

@@ -0,0 +1,10 @@
+// SKIP_TXT
+fun baz(options: String = ""): String = ""
+
+fun runForString(x: () -> String) {}
+
+fun foo(dumpStrategy: String) {
+    val dump0: () -> String = ::baz
+
+    runForString(::baz)
+}