tsType use export from npm package

I see from [this issue](https://github.com/bcherny/json-schema-to-typescript/issues/211) that using `tsType` with packages seems to be possible. However I cannot seem to get this to work. The import I want to define is

```ts
import { StreamableFile } from "@nestjs/common";
```
The [examples here](https://github.com/bcherny/json-schema-to-typescript/blob/master/test/e2e/customType.ts) only give basic examples of inbuilt Node exports

Start with test/e2e/customType.ts and compare its built-in Node export examples with the requested @nestjs/common import. Reproduce the configuration used for tsType and determine whether package imports are supported; done means a confirmed working case or a focused test documenting the failure.

Written by the indexing model from the issue text.