Prompt Book Errata Afteruse Mechanics

The mechanic is a state-pressure review: when a future reader consumes an old errata page, the review must keep source errata, prior cue block, proof bridge, beneficiary, harmed reader, and future effect visible.

Valid outcomes include scoped certification, source/original split, margin provenance annotation, harmed-reader notice, route annotation, quarantine, or false-clean default. False-clean default creates recovery-only future play rather than broad authority.