Fix: walk VB syntax tree in VbNameExprToCsExpr instead of ToString().Split('.')

Handle IdentifierNameSyntax, MemberAccessExpressionSyntax, and QualifiedNameSyntax
(which appears for Global.X references in default value context). Also remove
unnecessary Simplifier.Annotation since simplification is applied automatically
in a second phase.

https://claude.ai/code/session_01AkwUvu3XuCdj3D4axoX4UX

Author: claude

CodeConverter/CSharp/DeclarationNodeVisitor.cs

@@ -4,7 +4,6 @@
 using Microsoft.CodeAnalysis.CSharp;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Microsoft.CodeAnalysis.Editing;
-using Microsoft.CodeAnalysis.Simplification;
 using static Microsoft.CodeAnalysis.VisualBasic.VisualBasicExtensions;
 using ICSharpCode.CodeConverter.Util.FromRoslyn;
 using ISymbolExtensions = ICSharpCode.CodeConverter.Util.ISymbolExtensions;
@@ -733,16 +732,34 @@ private static ExpressionSyntax BuildCharExpressionFromVbSyntax(VBSyntax.Express
         // For char literal expressions (e.g. "^"c), use the constant value directly
         if (defaultValueNode.IsKind(VBasic.SyntaxKind.CharacterLiteralExpression)) {
             var constant = semanticModel.GetConstantValue(defaultValueNode);
-            if (constant.HasValue && constant.Value is char c) {
+            if (constant.HasValue && constant.Value is char c)
                 return CS.SyntaxFactory.LiteralExpression(CS.SyntaxKind.CharacterLiteralExpression, CS.SyntaxFactory.Literal(c));
-            }
         }
-        // For named constant references (e.g. DlM or Module.DlM), build a member access expression.
-        // Strip VB's "Global." prefix (VB global namespace qualifier, has no C# identifier equivalent).
-        // Annotate for simplification so Roslyn reduces e.g. TestModule.DlM → DlM within TestModule.
-        var parts = defaultValueNode.ToString().Trim().Split('.');
-        if (parts.Length > 1 && parts[0] == "Global") parts = parts.Skip(1).ToArray();
-        return ValidSyntaxFactory.MemberAccess(parts).WithAdditionalAnnotations(Simplifier.Annotation);
+        return VbNameExprToCsExpr(defaultValueNode);
+    }
+
+    private static ExpressionSyntax VbNameExprToCsExpr(VBSyntax.ExpressionSyntax vbExpr)
+    {
+        switch (vbExpr) {
+            case VBSyntax.IdentifierNameSyntax identifier:
+                return CS.SyntaxFactory.IdentifierName(identifier.Identifier.Text);
+            case VBSyntax.MemberAccessExpressionSyntax memberAccess:
+                // Skip VB's "Global." qualifier — it's VB's global namespace prefix, has no direct C# identifier equivalent
+                if (memberAccess.Expression.IsKind(VBasic.SyntaxKind.GlobalName))
+                    return CS.SyntaxFactory.IdentifierName(memberAccess.Name.Identifier.Text);
+                return CS.SyntaxFactory.MemberAccessExpression(CS.SyntaxKind.SimpleMemberAccessExpression,
+                    VbNameExprToCsExpr(memberAccess.Expression),
+                    CS.SyntaxFactory.IdentifierName(memberAccess.Name.Identifier.Text));
+            case VBSyntax.QualifiedNameSyntax qualifiedName:
+                // Qualified names (e.g. Global.TestModule) appear in name/type context within default values
+                if (qualifiedName.Left.IsKind(VBasic.SyntaxKind.GlobalName))
+                    return CS.SyntaxFactory.IdentifierName(qualifiedName.Right.Identifier.Text);
+                return CS.SyntaxFactory.MemberAccessExpression(CS.SyntaxKind.SimpleMemberAccessExpression,
+                    VbNameExprToCsExpr(qualifiedName.Left),
+                    CS.SyntaxFactory.IdentifierName(qualifiedName.Right.Identifier.Text));
+            default:
+                throw new NotSupportedException($"Unexpected VB expression in char default value: {vbExpr}");
+        }
     }
 
     private static bool IsThisResumeLayoutInvocation(StatementSyntax s)