16972 add assignee responsible to wp form

[``* `#16972` Support assignee/responsible property on work package forms and PATCH endpoint``](https://community.openproject.org/work_packages/16972)

Includes
- https://community.openproject.org/work_packages/17426
- https://community.openproject.org/work_packages/17432
- https://community.openproject.org/work_packages/17436

- [x] Path service
(You'd need to put it in parentheses)

On Thursday, November 27, 2014, Hagen Schink <notifications@github.com>
wrote:

> In
> lib/api/v3/work_packages/form/work_package_attribute_links_representer.rb:
>
> >
> > -                     represented.status_id = resource[:id] if resource[:ns] == 'statuses'
> > +                     represented.status_id = resource[:id] if resource
> > +                   }
> > +
> > +          property :assignee,
> > +                   exec_context: :decorator,
> > +                   getter: -> (*) {
> > +                     id = represented.assigned_to_id
> > +
> > +                     { href: id ? api_v3_paths.user(id) : nil }
>
> May looks more 'Ruby-ish' but isn't syntactically correct Ruby (just tried
> it to be sure). [image: :wink:]
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/opf/openproject/pull/2239/files#r20983266>.
>