对于“摘面具动作”生成的视频不正确


对于这个首尾帧，使用语句“First, raise your slender right hand without any clothes to cover it, and then slowly remove the mask with your hand. Don't let the mask disappear suddenly, show a smile.”生成的视频，面具直接消失

Reproduce the issue using the supplied first and last frames and the English prompt: the generated video should show the hand removing the mask rather than making it disappear suddenly. The payload names no files or tests, so begin by locating the video-generation entry point and add a regression check for this behavior.

Written by the indexing model from the issue text.