Tags & Metadata on Compound Docs

This epic will define how tagging and metadata are handled on Compound docs

The basic concept is the following:

I need the metadata from all my children files to be accessible via my parent, such that I can search for parent files only but get complete results

I need any tags to be applied to both the children and the parent, but all be accessible via the parent

I want to search for assets that are child components of compound assets; searching/filtering on normal fields (e.g. expiration date) and then filtering to only assets that are children of compound documents. Then select one and view all the parent docs the component is used in. 

Then I want to perform an action on that complete set of parents (e.g. change metadata/lifecycle status, add all to collection - actions TBD per UCs). E.g. We know some assets are going to expire next month, we must search for them, then flag them to review and then replace the children in all the designs that use them. Maybe the action edits a field value or creates a collection of all the compounds that need updating. E.g. We’re no longer working with athlete X, so find all assets that are linked to that talent, then for each find all the compounds that use that asset and run an action on them (collection, WF, collection, notification).