[FIR] Missing NESTED_CLASS_ACCESSED_VIA_INSTANCE_REFERENCE

^KT-59433 Fixed

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/FirCallResolver.kt

@@ -352,7 +352,7 @@ class FirCallResolver(
                     referencedSymbol,
                     qualifiedAccess.source,
                     qualifiedAccess.typeArguments,
-                    diagnostic,
+                    diagnostic ?: extractNestedClassAccessDiagnostic(nameReference.source, qualifiedAccess.explicitReceiver, referencedSymbol),
                     nonFatalDiagnostics = extractNonFatalDiagnostics(
                         nameReference.source,
                         qualifiedAccess.explicitReceiver,

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/QualifiedNameResolution.kt

@@ -21,6 +21,7 @@ import org.jetbrains.kotlin.fir.resolve.BodyResolveComponents
 import org.jetbrains.kotlin.fir.resolve.calls.getSingleVisibleClassifier
 import org.jetbrains.kotlin.fir.resolve.createCurrentScopeList
 import org.jetbrains.kotlin.fir.resolve.diagnostics.ConeDeprecated
+import org.jetbrains.kotlin.fir.resolve.diagnostics.ConeNestedClassAccessedViaInstanceReference
 import org.jetbrains.kotlin.fir.resolve.setTypeOfQualifier
 import org.jetbrains.kotlin.fir.symbols.impl.FirClassLikeSymbol
 import org.jetbrains.kotlin.name.ClassId
@@ -184,6 +185,16 @@ private fun FqName.continueQualifierInPackage(
     }
 }
 
+internal fun extractNestedClassAccessDiagnostic(
+    source: KtSourceElement?,
+    explicitReceiver: FirExpression?,
+    symbol: FirClassLikeSymbol<*>
+): ConeDiagnostic? {
+    if ((explicitReceiver as? FirResolvedQualifier)?.typeArguments?.isNotEmpty() == true)
+        return ConeNestedClassAccessedViaInstanceReference(source!!, symbol)
+    return null
+}
+
 internal fun extractNonFatalDiagnostics(
     source: KtSourceElement?,
     explicitReceiver: FirExpression?,