Metadata overlay (7660)

These changes revise and refactor the metadata overlay (popup box) on item story and theme pages.

Tasks include:
* Move the metadata overlay logic from the views to a helper ([#7562](https://issues.dp.la/issues/7652))
* Display intermediateProvider and dataProvider together with the label "Contributing Institution" ([#7628](https://issues.dp.la/issues/7628))
* Display edmRights with the label "Standardized Rights Statement" ([#7662](https://issues.dp.la/issues/7662))
* Add a link to view the item in the portal ([#7661](https://issues.dp.la/issues/7661))
* When the API returns Array values for fields (such as dataProvider or sourceResource.description), parse them correctly so that they display in the metadata overlay (before they were not displaying) ([#7659](https://issues.dp.la/issues/7659))

These individual tasks are organized in Redmine under the meta-task [#7660](https://issues.dp.la/issues/7660)
The individual tasks in Redmine have file names and line numbers that point to changes specific to each task.
Please also see [#7562](https://issues.dp.la/issues/7652) for additional notes about some peripheral changes.