export StateUpdater and other utility types

[bennypowers]

consider:

const setWith = (setter: StateUpdater<string>) =>
  ({ target: { value } }) =>
    setter(value);

function AddUser(this: ApolloMutationElement) {
  const [mutate, { data, error, loading }] = useMutation(AddUserMutation);

  const [name, setName] = useState('');
  const [twitter, setTwitter] = useState('');

  return html`
    <mwc-textfield label="Name" value="${name}" @input="${setWith(setName)}"></mwc-textfield>
    <mwc-textfield label="Twitter handle" value="${twitter}" @input="${setWith(setTwitter)}"></mwc-textfield>
  `;
}

customElements.define('add-user', component(AddUser));

In cases like these it would be nice to just

import type { StateUpdater } from 'haunted';