Can it fail if no types are found?

As a library author I very much like `attw` as it allows me to check if my "main" entry point is correct. However, I noticed that the `attw` CLI doesn't fail if no types are found at all. It simply states:

```bash
{
"packageName": "trading212-api",
"packageVersion": "1.0.2",
"types": false
}
```

Is there the possibility to make `attw` fail also when there are no types at all?

Start by reproducing the attw CLI result shown for trading212-api, where the JSON reports "types": false. Trace where this result is converted into the CLI outcome and check how other failure cases are handled. Done means the CLI fails when no types are found while preserving the reported result.

Written by the indexing model from the issue text.