fix: not working explicits exports for types on declaration files

Author: danielpza

src/index.ts

@@ -159,7 +159,7 @@ const transformer = (_: ts.Program) => (context: ts.TransformationContext) => (
       visitNamedExports as any,
       ts.isNamedExports
     );
-    return node.exportClause === exportClause || exportClause
+    return node.exportClause === exportClause || exportClause || isDeclarationFile
       ? ts.updateExportDeclaration(
           node,
           node.decorators,

tests/__fixtures/core/index.ts

@@ -1,4 +1,5 @@
 export { sum } from "@utils";
+export { NoRuntimecodeHere } from "@utils/types-only";
 import { subs, NoRuntimecodeHere } from "@utils";
 import "@circular/b";
 import { A } from "@circular/a";