DR-071 — Memtrace complements the code-intelligence stack; GitNexus remains the impact/rename authority

Memtrace must NOT gate the impact-before-edit / detect-changes / rename discipline: its TS cross-file call-edge resolution is materially incomplete on this repo (get_impact on getAuthorisedClient → 18 test-fixture callers vs GitNexus’s correct 151 production routes). Adopted additively only: review_github_pr as an optional PR pass and find_code as NL-search fallback. Re-evaluate when call-edge resolution is fixed (re-test expects ~150 real callers). Note: the vendor-managed ~/.claude/MEMTRACE.md directs impact analysis to Memtrace and reinstalls itself — this ruling is what breaks the tie.

(Swept unrecorded at ec9fcfde; re-accepted by owner ruling S499 — the S499 tombstone audit found it still binding with no other home.)