Clone snapshot doesn't load reference files into FILE SFT impl

After cloning a snapshot from a FILE SFT enabled table, noticed that none of the cloned table files were added into the FILE SFT meta files, in fact, FILE SFT meta dir didn't even got created. Scanning this cloned table gives no results, as none of the files are tracked. I believe we need to call StoreFileTracker.add during the snapshot cloning.