elm adapter

Would be cool to have a straight forward way to expose `nanocomponent` adapters into `elm-lang`.

cc/ @terezka, any suggestions on how to best achieve this? Any pointers or examples would be extremely helpful :sparkles: - thanks!

#### See Also
- https://guide.elm-lang.org/interop/javascript.html

Start by reading the linked Elm JavaScript interop guide and reviewing the repository's existing adapters. The issue does not identify files, tests, or a settled design, so first determine the intended adapter API and integration boundaries. Done means there is an agreed, working way to expose nanocomponent adapters to Elm.

Written by the indexing model from the issue text.