Remove stale video from nest anchor element

Editor assessment

A well-scoped fix: 'remove stale video from nest anchor element' is specific, imperative, lowercase, and short, with the curriculum scope correctly identifying the affected content area. It reads naturally in git log and would group cleanly under fix(curriculum) in release notes. The phrasing is slightly off grammatically — 'the nest anchor element' or 'nested anchor' would be smoother — and the subject does not say why the video was stale, though for a fix this small that context is optional. No body is acceptable here. A good example of a proportionate, conventional commit message.