Create Propagation Watch

The propagation watch's terms. Validation is normalize_probe_name's.

window_hours is bounded at the MODEL so an out-of-range window is refused during parse — the metered-422 handler covers that leg, and a bound checked later would price a window we do not sell. The bound is the one the surface's published input_schema advertises (1 to 24), not a wider one: a machine contract that under-states what it accepts is drift, and a sub-hour window would pro-rate toward a $0 offer on an always-paid surface.

The minted handle plus the terms it was sold on.

Deterministic throughout: an echo of what the buyer asked for, the price that was settled, and where to poll. No prose, no record, no prescription — the D94 invariant carries onto every watch surface.