fix shorten IA for new IA API

Shorten IA is currently broken (see https://duckduckgo.com/?q=shorten+https%3A%2F%2Fdylansserver.com), this fixes it.

Also should probably close this: https://duck.co/ideas/idea/1199/shortening-url-service (although I second a ddg.gg service).
@nospampleasemam we actually no longer use `header1` (I'm surprised it still works!), please change that to `name`