[LL FIR] do not reanalyze non-top level properties with initializer

Treat changes inside non-top level property initializer as OOB
It is OOB because CFG for a class depends on a property initializer,
so we must rebuild CFG for the class

Also, this commit makes the API more understandable

^KT-59687

analysis/low-level-api-fir/testdata/fileStructure/classMemberProperty.kt

@@ -7,5 +7,5 @@ class X {/* NonReanalyzableClassDeclarationStructureElement */
 
     val y = 42/* NonReanalyzableNonClassDeclarationStructureElement */
 
-    var z: Int = 15/* ReanalyzablePropertyStructureElement */
+    var z: Int = 15/* NonReanalyzableNonClassDeclarationStructureElement */
 }