Fix bug that prevents workspace app from being updated when source content has been deleted from workspace

I have identified what is a potentially catastrophic bug that requires a solution soon.

When a report or model in a workspace is deleted and that report was added to an audience in the workspace app, users are not able to update the app, including just deleting the audience that report was included in, because the report no longer exists. The only solution I found was to "Unpublish" the app, which is essentially deleting the app, with all its audiences. This is potentially a huge failure especially for a production app with many audiences across many users.

One or both of the following solution ideas should be implemented:

1) Prevent users from deleting reports or models without first removing them from the app, and/or

2) Make "Unpublish" the app, merely take the app offline, but retain all its audiences, reports and permissions, but allow the developer to remove the deleted report, and then republish the app with the same permalink, and unaffected audiences/permissions still in place.

Its only a matter of time before this causes a very big problem in our very large organization.

Cheers.