verify(P3): dead-code-and-stale-prefix-cleanup — 4-layer verify PASS + ship

VERIFY: structural — dead export + stale comments + prefixes gone; behavioral — 616 tests + CI PASS; quality — env-override test updated.

---ci---
project: acdl
phase: 3
milestone: v1.16
status: complete
phase_role: execution
requirements:
  covered: [REQ-167]
  partial: []
---/ci---

scripts/run_pattern_plan.sh

@@ -26,7 +26,7 @@ done
 CONTRACT="contracts/$MODULE.yaml"
 [ -f "$CONTRACT" ] || { echo "FAIL: no sample contract at $CONTRACT for module '$MODULE'" >&2; exit 1; }
 
-WORK="/tmp/acdl_pattern_plan_$MODULE"
+WORK="/tmp/nova_pattern_plan_$MODULE"
 rm -rf "$WORK"; mkdir -p "$WORK"
 
 echo "=== Pattern plan: $MODULE ==="