[Bug]: [http-server-csharp] model that extends another model with no additional properties are not emitted as C# class

[k117117117]

Describe the bug

Subject says it all
I describe the bug in Reproduction section

library versions
PS F:\Dev\typespec-issue> npm list
typespec-issue@0.1.0 F:\Dev\typespec-issue
├── @typespec/compiler@1.6.0
├── @typespec/http-server-csharp@0.58.0-alpha.22
├── @typespec/http@1.6.0
├── @typespec/openapi@1.6.0
├── @typespec/openapi3@1.6.0
└── @typespec/rest@0.76.0

Reproduction

main.tsp

import "@typespec/http";

using Http;
@service(#{ title: "FooBarBaz Service" })
namespace DemoService;

model Foo {
  id: int32;
  name: string;
}

model Bar extends Foo {
  code: string;
}

model Baz extends Foo {}

interface FooBarBazService {
  @route("/foo/{id}") @get
  getFoo(id: int32): Foo;
}

model Baz should be emitted as Baz.cs, but not be emitted

I think model Baz should be emitted as Baz.cs into generated/models/Baz.cs, like this

because I want to write some code in handwritten partial class

Checklist

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• Check that there isn't already an issue that request the same bug to avoid creating a duplicate.
• Check that this is a concrete bug. For Q&A open a GitHub Discussion.
• The provided reproduction is a minimal reproducible example of the bug.