Phase contracts

The platform's core bet is that an outcome is guaranteed by the ENGINE, not left to the model's discretion. This is that bet counted: for each declared Phase, what holds it to its promise. Ungoverned is not automatically wrong — a routing or meeting phase may honestly need no envelope — but it has to be visible. The same applies to WHICH SKILL a phase runs: a phase with no declared UsesSkill does not fail, it guesses — the orchestrator keyword-scores the roster, so the phase can silently run a different capability than its Goal describes.