Change authors type to include Open Doors projects

When works are archived as part of an [Open Doors ](https://archiveofourown.org/users/Open_Doors/collections) project they can have a different format for the author, e.g.
> [Bah Humbug](https://archiveofourown.org/collections/twicebitten/works/35166544) by LLN-RookattheDoor [archived by [twicebitten_archivist](https://archiveofourown.org/users/twicebitten_archivist/pseuds/twicebitten_archivist)]

A proposed type for this use-case is:
```js
{
username: null,
pseud: "LLN-RookattheDoor",
}
```
An `archivedBy` property should also be added.