Add the `deleted` property to the root of the Response object to communicate if the delete action was successful. Move the state of the resource prior to the delete request under a new `previous` property. As a result DELETE responses are now structured like so:
`{ deleted: true, previous: { ... } }`
Also includes helpful information to DELETE requests for resources that are not trashable.
Props timmydcrawford, rmccue, jnylen0.
Fixes#38494.
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