Datasets:
Merge natural_video_density into natural_video. The two configs described the same 1028 clips with disjoint question sets, so they are now one config of 1813 rows, with a `question_set` column ('designed' / 'density_topup') telling them apart; natural_video_density is deleted. No media moves. The merge also brings the designed questions up to the same notation: source_provenance is now on all 1813 rows (950 EPIC rows shipped null), question_time is length_L rather than 0.0, and density_band, event timing, clip_sha256, query_class and label_source are populated wherever the source supports it. Fixes clip_sha256, which was resolved by clip basename: 637 basenames are reused across the per-length directories, so 465 rows carried the hash of a different length's file, breaking the documented group-on-clip_sha256 recipe. README, LICENSES and Croissant metadata regenerated for the single natural config (2.2.0).
1f3b81c verified