If you create a new project in a solution that uses file-scoped namespaces the classes created by the project template should also use file-scoped namespaces.

Similar to #3930, which only handled new item templates (which work fine).

Repro steps:

1. Create a new repository/solution with an EditorConfig file. Make sure the EditorConfig file contains csharp_style_namespace_declarations = file_scoped:suggestion.
2. Create a new project that contains at least one class with a namespace (e.g. class library or WPF application).
3. See that the namespace in the generated class file uses the old block scoped style and that IDE0161 "Convert to file-scoped namespace" is triggered immediately.

• According to Console/Class lib project templates use latest C# language idioms #3360 this should be fixed for class libraries, but I can still reproduce it.
• According to ASP.NET Core project templates use latest C# language idioms aspnetcore#33947 this should be fixed for ASP.NET Core, but I can still reproduce it.
• WPF seems to be still open: WPF project templates use latest C# language idioms wpf#4774
• (I didn't test other templates)

Tested with Visual Studio 2022 17.0.6