Scrub Stale Documentation into CLAUDE.md Router

Use context architecture skill to scrub all old documentation, including instructions, specs, trackers, ADRs - delete everything superseeded and stale, remove references to historical decisions, delete duplicates, single home everything and make sure all documentation is accessible from CLAUDE.md router in a few steps

Docs scrub merged (PR #5300): removed provenance/task citations, restated mechanics, stale lines across 8 docs; context check + quick gate + CI green. Deferred: further ADR trims, risk-register dates. Jaah Deploy not watched.