recording.viser: include sam3d object meshes (fix stale ply_path); README: viewer:false + snapshot_download docs

Refresh: 48 clips with full descriptions + viser recordings

Refresh scene.json: surface Action100M action_detailed / summary / video_title; sync index.json

Refresh dataset: 48 trim-reviewed clips, manual SAM3 prompts, full descriptions in scene.json

Switch mask.mp4 to RGB cutout of SAM-tracked objects

Initial deploy