Image stacks inside partials have HTML that is sometimes incorrect

The stack correctly exports the image, but the HTML generated doesn't always point to the correct place.

The HTML generated always points to the path of the files directory for the first time the partial was rendered to preview or rendered for publish. After this point the path is compiled in and rendered without adjustment.

There is no meta template created for the files path. Finding the use of the RW API filesFolderPath and using Stacks' exportAssetpath instead.

It would probably be good to remove the passthrough for filesFolderPath so that nodes can't use it, because it seems like it's always going to be problematic for this same reason.