process-gap: POL-001 scope unclear for INDEX artifacts (BC-INDEX changelog convention)

Deferred from Pass-10 convergence-close of S-BL.ROUTER-ADDR (BC-5.39.001 satisfied, 3/3 clean fresh-context 3-lens).

**Finding:** `BC-INDEX.md` (`.factory/specs/behavioral-contracts/BC-INDEX.md`) does not record BC-2.06.003 v1.12/v1.13/v1.14/v1.15 bumps in its own changelog, despite a clear convention established by the earlier BC-2.02.003 rows (v2.0/v2.1/v2.2) that BC-INDEX should track when downstream BCs it indexes are bumped. POL-001 changelog-completeness wording is ambiguous whether INDEX artifacts are required to record downstream artifact bumps or whether they are exempt from that obligation.

**Impact:** Consistency validators and spec reviewers cannot determine whether a missing BC-INDEX changelog row is a genuine omission or a policy-permitted omission. In practice this caused low-confidence findings during adversarial review that consumed triage time.

**Proposed clarification:** POL-001 should state explicitly whether INDEX artifacts (e.g. BC-INDEX.md, STORY-INDEX.md) must record downstream artifact bumps in their own changelogs. If exempt, add a note to the INDEX artifact template; if required, add an enforcement check to the consistency-validator prompt.

**Severity:** LOW / non-blocking
**Source:** adversarial review Pass-10, lens-3 (governance / traceability lens)
**Affected project:** ArcavenAE/switchboard-blue (observed during Wave-6 Tranche B)

Non-blocking per pr-manager triage. Filed as follow-up per orchestrator cycle-closing checklist.