[compiler] introduce dedicated Fir declaration for dangling modifier lists (KTIJ-23008)

ensure fir annotations are included in FirDanglingModifierList and resolved,
dedicated DanglingTopLevelModifierListStructureElement exists for top
level lists only, class level lists are processed by containing structure
element

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/FirTreeBuilder.kt

@@ -118,6 +118,7 @@ object FirTreeBuilder : AbstractFirTreeBuilder() {
     val errorExpression by element(Expression, expression, diagnosticHolder)
     val errorFunction by element(Declaration, function, diagnosticHolder)
     val errorProperty by element(Declaration, variable, diagnosticHolder)
+    val danglingModifierList by element(Declaration, declaration, diagnosticHolder)
     val qualifiedAccessExpression by element(Expression, expression, qualifiedAccess)
     val qualifiedErrorAccessExpression by element(Expression, expression, diagnosticHolder)
     val propertyAccessExpression by element(Expression, qualifiedAccessExpression)

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/ImplementationConfigurator.kt

@@ -43,6 +43,7 @@ object ImplementationConfigurator : AbstractFirTreeImplementationConfigurator()
         }
 
         impl(anonymousObject)
+        impl(danglingModifierList)
         noImpl(anonymousObjectExpression)
 
         impl(typeAlias)

compiler/fir/tree/tree-generator/src/org/jetbrains/kotlin/fir/tree/generator/NodeConfigurator.kt

@@ -456,6 +456,10 @@ object NodeConfigurator : AbstractFieldConfigurator<FirTreeBuilder>(FirTreeBuild
             +field("dispatchReceiverType", coneSimpleKotlinTypeType, nullable = true)
         }
 
+        danglingModifierList.configure {
+            +symbol("FirDanglingModifierSymbol")
+        }
+
         file.configure {
             +field("annotationsContainer", fileAnnotationsContainer).withTransform()
             +field("packageDirective", packageDirective)