Out of curiosity, why `new Logger` here (every time error occurs)?

now that this isn't private anymore, what about renaming it to `handleError`?

```suggestion body.getStream().once('error', (err: Error) => { ``` to prevent the error 'Cannot set headers after they are sent to the client' if for whatever reason the _error_ event is emitted multiple times (not sure if this is possible tho)

```suggestion export interface StreamableHandlerResponse { ```

```suggestion protected handler: (err: Error, response: StreamableHandlerResponse) => void = ( ``` so others can customize this one