GitHub previews multi-model orchestration for Copilot CLI coding tasks

GitHub's Project HydraFusion is a research preview that builds a custom workflow for each coding task rather than routing to one fixed model. It chooses between three execution patterns: a single model, a cascade with a quality gate, or a critique pattern using a read-only cross-family reviewer model.

Why it matters: This reflects a broader shift in coding assistants away from picking a single model toward dynamically composing multiple models per task, an approach other agentic coding tools have also been experimenting with. If it works well, it could push competitors to treat model orchestration, not just model choice, as a core product surface.