[FIR2IR] Expand typealiases before inserting implicit casts

^KT-59461 Fixed
^KT-59464

compiler/testData/codegen/box/fir/flexibleStaticConstantFromJava.kt

@@ -0,0 +1,19 @@
+// TARGET_BACKEND: JVM
+// ISSUE: KT-59461
+
+// FILE: NullContainer.java
+public interface NullContainer {
+    static String NULL = null;
+}
+
+// FILE: main.kt
+typealias NullableString = String?
+
+fun updateThreadContext(): NullableString {
+    return NullContainer.NULL
+}
+
+fun box(): String {
+    updateThreadContext()
+    return "OK"
+}