Per-title encoding optimization

Design the per-title (and per-shot) encoding-optimization service that decides the ABR ladder for each title rather than using one fixed resolution/bitrate ladder for the whole catalog. A flat ladder over-spends bits on simple content (a talking-head cartoon) and under-delivers on complex content (a fast-action sports clip). The service must analyze each title's complexity, choose the rungs (resolution+bitrate pairs) that sit on the quality-vs-bitrate convex hull, and do it cheaply enough to run on every one of millions of titles.