FIR: add status line to all failing black box tests

compiler/testData/codegen/box/enum/declaringClassOnEnumObject.kt

@@ -1,5 +1,6 @@
 // TARGET_BACKEND: JVM
 // IGNORE_BACKEND_FIR: JVM_IR
+// FIR status: UNRESOLVED_REFERENCE (declaringClass). See https://youtrack.jetbrains.com/issue/KT-49653. To be discussed.
 package test
 
 enum class KEnum { A }

compiler/testData/codegen/box/enum/javaEnumValues.kt

@@ -1,5 +1,8 @@
 // TARGET_BACKEND: JVM
 // IGNORE_BACKEND_FIR: JVM_IR
+// FIR status: V
+// Caused by: java.util.NoSuchElementException: Sequence contains no element matching the predicate.
+// at org.jetbrains.kotlin.backend.jvm.lower.MappedEnumWhenLowering.visitClassNew(MappedEnumWhenLowering.kt:232)
 // FILE: E.java
 public enum E {
     A();

compiler/testData/codegen/box/enum/nameClashWithCompanion.kt

@@ -1,5 +1,6 @@
 // TARGET_BACKEND: JVM
 // IGNORE_BACKEND_FIR: JVM_IR
+// FIR status: don't support legacy feature (see https://youtrack.jetbrains.com/issue/KT-37591). UNRESOLVED_REFERENCE at '+'
 // WITH_STDLIB
 // MODULE: lib
 // FILE: lib.kt