This allows adding of pinboard items to a timeline. I'm hoping we can get this in for Maniphest (Pholio, Cover Image) and Macro (because, Macro), but unsure how to scalably do this. Anyways, here's the front end.
Yeah I started to force something into transactions but realized it'd bite me in the end if it wasn't scalable. At least pinboard for image display should work in most/all cases and case be tweaked as needed (lightbox).