Cut a long video down to selected source ranges (montage / clip assembly). Part of the video-recap bundle: in the orchestrated (two-pass) flow, consumes clip_plan.json + the source video, produces edited_source.mp4; the agent then writes narration.json against the output timeline. When invoked standalone WITHOUT --no-narration-map, also remaps an existing narration.json → narration_mapped.json (legacy single-pass path). 触发词: 视频剪辑, 剪辑式解说, video cut, clip plan, 拼剪.
