Attach original (non proxied) input in DEV mode

Or give access as a third argument to mini functions.

Use case:

```js
const transformEvent = traph({
  id: i => i.qid::pipe(Number),
  timestamp: i => millisToSec(Number(i.starttime)),
  severity: i => Number(i.magnitude),

  // We often need the original data in debug, 
  // but here is passed as Proxy and not very comfortable!
  _original: (i) => i,
})
```

