phase 1.6 BIPA: scrum-driven fixes

Per 2026-05-03 phase_1_6_bipa_gates scrum (13 findings, 0 convergent).
1 BLOCK verified false positive, 4 real fixes shipped:

False positive (verified):
- opus BLOCK on attest:55 — claimed `set -uo pipefail` without `-e`
  makes the post-python3 `if [ $? -ne 0 ]` check unreachable. Verified
  WRONG: `X=$(false); echo $?` prints 1. Bash propagates command-
  substitution exit through $? on the assignment line. The check IS
  the python3 exit gate. Inline comment added to the script noting
  the false positive so future scrums don't re-flag.

Real fixes:
1. opus WARN attestation:18 — schema fingerprint hashed names ONLY,
   missing column-type changes. A column repurposed to hold base64
   photo bytes under its existing name would pass undetected. Now
   hashes "name<TAB>type<TAB>nullable=bool" per row. Re-run produced
   evidence SHA-256 1fdcc9f1... (vs old 230fffeb..., reflecting the
   broader fingerprint scope).

2. opus WARN gate_4_test:60 — definition regex didn't catch
   object-literal property forms (`const t = { FEMALE_NAMES: [...] }`)
   or TypeScript class fields (`class L { public NAMES_X: string[] = [] }`).
   Added two new patterns + a regression test
   (Gate 4: object-literal and class-field bypasses are caught) that
   exercises 5 bypass forms. 4/4 tests green; 1 minor regex tweak
   needed mid-fix to handle single-line class bodies.

3. kimi WARN python3-reliance — script assumed pyarrow installed and
   would emit a stack trace into the attestation if not. Added
   `python3 -c "import pyarrow"` gate at top with clean install
   instructions on failure.

4. opus INFO PHASE_1_6:200 — item 7 (training) silently dropped from
   blocking set with bare "deferred" rationale. Now explicitly states
   the deferral is conditional on small operator population (J + 1-2
   named ops); item 7 re-promotes to blocking if population grows.
   ⚖ COUNSEL marker added.

Skipped (acceptable as ⚖ COUNSEL placeholders by design):
- kimi WARN consent template:30-day-SLA (counsel decides number)
- kimi WARN consent template:email-placeholder (counsel supplies)
- kimi WARN parquet absence (env override exists; redeployment-aware)
- kimi INFO runbook manual-erasure (marked TODO when /erase ships)
- qwen INFO doc path/status nits (already addressed by file moves)

Tests: 4/4 Gate 4 absence test (incl. new bypass-coverage), 3/3
attestation evidence checks pass on live data.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/PHASE_1_6_BIPA_GATES.md

@@ -199,7 +199,17 @@ PLUS:
 | 6 | Cryptographic attestation pre-identityd | DONE — `scripts/staffing/attest_pre_identityd_biometric_state.sh` + `docs/attestations/BIPA_PRE_IDENTITYD_ATTESTATION_2026-05-03.md` (3/3 evidence checks pass; signature lines pending) | pending signature | **eng-DONE, signature-pending** |
 | 7 | Employee training material | scaffold deferred — Gate 5 runbook §7 acknowledgment may serve as substrate | pending | **deferred** |
 
-Until items 1-5 + 6 are checked off, **identity service backfill (Phase 2 §5 Step 5) cannot proceed.**
+**Blocking set for Phase 2 backfill:** items **1, 2, 3, 4, 5, 6** must
+all be DONE. Item 7 (employee training) is reduced from blocking to
+"deferred" because the Gate 5 destruction runbook §7 already requires
+operator acknowledgment before legal-tier credentials are issued —
+that acknowledgment is procedurally equivalent to the training-record
+requirement when the operator population is small (J + 1-2 named
+operators). If the operator population grows beyond that, item 7
+re-promotes to blocking and a separate training program must be authored.
+
+⚖ COUNSEL — confirm whether item 7 deferral is acceptable for the
+expected operator population size, or restore it to the blocking set.
 
 **Calendar bottleneck:** Items 1, 2, 5, 6 (and #7) await counsel
 review of the engineering scaffolds. Gate 3 (photo-upload endpoint)