Replaces the 3-row media preview with one video-layout RGB/depth/mask still per MOS phase. Removes the old 3-file video preview folder to avoid confusion. Existing README teaser and jumbotron assets remain unchanged.
Replaces binary media preview configs with a small CSV config containing direct preview image/video links, avoiding Dataset Viewer CSV parsing of binary files. Existing teaser and jumbotron assets remain unchanged.
