Add attempt count in the try function

It would be cool to be able to find out which attempt is currently underway. In my case, I want to send users a toast with information.

```ts
const result = await Result.tryPromise(
  ({ attempt }) => func(attempt),
  {
    retry: {
      times: 5,
      delayMs: 1000,
      backoff: 'constant',
    },
  },
)
```