AgentPlayback 1.1.0

Adds a How it works card beside the dashboard legend, opening a local video walkthrough with playback controls. The walkthrough begins five seconds into the original video.

The local server now supports MP4 media types and byte-range requests for seeking. The video player opens outside the scaled dashboard to avoid black playback when reopening it.

Validated with a production build, npm package contents, real CLI browser playback and reopening, and HTTP range/HEAD checks.