Spec Kitty

Mission Run: Mission-Type Single-Source + Gate Wiring

Make the mission-type roster single-sourced and the cross-grain integrity gate load-bearing outside pytest.

A follow-up bundle that closes four gaps left by the mission-type unification work: it routes every hardcoded mission-type roster through the one doctrine source of truth, makes malformed doctrine indexes fail loudly instead of silently degrading, wires the cross-grain duplicate scan into a real runtime check, and promotes a private path accessor to a public seam. The effect: a newly-shipped mission type is picked up everywhere automatically, and a broken or colliding doctrine configuration can no longer pass unnoticed.