Builder internal class constructor rewrite issue [Workaround]

Current Workaround
========
Thanks to new c# syntax rewrites nicely as type can be omited.

```c#
public class Ghost{
public Ghost MyBuilderFunc()
{
return new /*Remove Class name*/(/*params*/);
}
}
```

Issue
====

```c#
public class Ghost{
public Ghost MyBuilderFunc()
{
return new Ghost(/*params*/);
}
}
```
rewrites to and fail as class mismatch
```c#
public class Ghost__Patched{
public Ghost__Patched MyBuilderFunc()
{
return new Ghost(/*params*/);
}
}
```

No file or test is named in the issue. Start by locating the code-rewrite path that patches class names and handles constructor expressions, then reproduce the shown Ghost example; done means the rewritten class and return type remain consistent without relying on the workaround.

索引モデルが issue の本文から書いたものです。