* refactor(prompt): platform-hint diet — shared _MEDIA_NATIVE spine; seven heavies compressed with every verified fact intact (3,175 -> ~2,520 map total, -657) * refactor(prompt): steer-channel note diet 225 -> 155 — marker is self-describing since its own provenance+replay clauses; prompt keeps only anti-lookalike + authority + latest-results scope (#40240/#76805 archaeology in comment)