Use case 6: Validate target scope/collection names

Users can select source scopes and collections from checkboxes. However, they have to manually type in scopes and collection names on the target. It's possible that they have entered a typo and the target scope/collection name is incorrect. There's currently no way to check for those.

A potential solution is to provide a on-demand "Validate" action where the XDCR can return the latest fetched target manifest for the UI. Any invalid mappings caused by invalid target scope/collection could be highlighted red.