refactor: group regex modification

LanguageRecogniser/Cpp/CppClassDiagramVisitor.cs

@@ -122,14 +122,14 @@ public class CppClassDiagramVisitor : CPP14ParserBaseVisitor<object>
                         if (aggregationMatch.Success && !string.IsNullOrEmpty(aggregationMatch.Groups[3].Value))
                         {
                             // Aggregation type
-                            string? typeName = aggregationMatch.Groups[2].Value; // Second capturing group
+                            string? typeName = aggregationMatch.Groups[3].Value; // Second capturing group
                             _classes.Last().Value.AddAssociation(typeName, actualAccessSpecifier,
                                 AssociationType.Aggregation);
                         }
                         else if (compositionMatch.Success && !string.IsNullOrEmpty(compositionMatch.Groups[2].Value))
                         {
                             // Composition type
-                            string? typeName = compositionMatch.Groups[2].Value; // Second capturing group
+                            string? typeName = compositionMatch.Groups[3].Value; // Second capturing group
                             _classes.Last().Value.AddAssociation(typeName, actualAccessSpecifier,
                                 AssociationType.Composition);
                         }