Add knowledge/best-practices.json: a machine-readable, provenance-stamped, schema-validated best-practices register — the source of truth for the upcoming v5.7 optimization lens (CA-OPT). 13 seed entries migrated from the v5.5 V-rows (loading-model + compaction facts) and the Anthropic 'Steering Claude Code' blog (mechanism-fit rules); each entry carries source.url + verified date + confidence. Only confirmed claims are user-facing (Verifiseringsplikt).
scanners/lib/best-practices-register.mjs: zero-dependency loader + validator (loadRegister/validateRegister/getEntry, native JSON.parse — not YAML, since the repo is zero-dep and yaml-parser.mjs can't parse arrays-of-objects). tests/lib/best-practices-register.test.mjs: 22 tests (schema, provenance integrity, negative cases, lookup).
Byte-stable: no scanner consumes the register yet (Chunk 2), so all scanner output is unchanged. Suite 1023->1045, self-audit A/A, readmeCheck passed. Full design: docs/v5.7-optimization-lens-plan.md.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
