type only exports of classes are not respected

[brc-dd]

Checklist

• [x] I can reproduce this issue when running this plugin on its own. Other plugins, such as node-resolve are known to cause issues.
• [x] I am running this plugin on .d.ts files generated by TypeScript. The plugin can consume .ts and even .js files (with allowJs: true), but this is known to cause issues.
• [x] This issue is not related to rolling up @types. The plugin ignores these by default, unless respectExternal is set. @types can contain hand-crafted code which is known to cause issues.

Code Snippet

declare class Foo {
  bar: string;
}

export type { Foo };

Actual Output

declare class Foo {
  bar: string;
}
export { Foo };

Expected Output

declare class Foo {
  bar: string;
}
export type { Foo };

Additional Context

It works if I alias my class as a type instead:

declare class _Foo {
  bar: string;
}

type Foo = _Foo;

export type { Foo };

Output

declare class _Foo {
  bar: string;
}
type Foo = _Foo;
export type { Foo };