fix(ms-ai-architect): Enhet 3b — dedup dual-**Dato:** i 5 mlops-genaiops-filer (Created-relabel/drop, git-verifisert) [skip-docs]

Løser dual-header der filer bærer BÅDE **Dato:** (opprettelse) OG **Last updated:**
(endring). Ground truth 2026-07-16 + git first-commit-map (2026-04-08 for alle 5):

- 4 distinkte (**Dato:** 2026-02-04, FØR git first-commit → ekte opprettelsesdato):
  relabel **Dato:** → **Created:**, verdi byte-bevart (norsk→engelsk label-rename).
- 1 identisk (mlops-security-access-control: **Dato:**=**Last updated:**=2026-06-19,
  ETTER git first-commit → metadata-artefakt, ikke ekte opprettelsesdato): drop redundant
  **Dato:**. Relabel ville påstått falsk opprettelsesdato — drop er sannferdig.

Ny ren primitiv dropRedundantBoldField (kaster uten identisk-verdi bevis-felt),
gjenbrukt relabelHeaderDialect m/ CREATED_MAP. Manifest-drevet dedup-dato.mjs med
hard per-fil-invariant FØR skriv (relabel: 1 linje, kun label-token; drop: net -1,
Last updated bevart), atomicWriteSync, idempotent. Ingen validator håndhever lukket
feltliste → **Created:** er additiv/konform.

+15 tester (dropRedundantBoldField, CREATED_MAP-relabel, applyOp, manifest, 2 corpus-
guards) + oppdatert stale Enhet-2 carve-out-guard til post-3b-sannhet. Suite 910/910
exit 0. validate-plugin 250 PASS/0 FAIL. Datoløse dual-**Dato:**-filer 5→0.

scripts/kb-update/lib/transform.mjs

@@ -500,6 +500,52 @@ export function dropRedundantPlainField(content, label) {
   return lines.join('\n');
 }
 
+/**
+ * Remove a bold header field — `**<dropLabel>:** <value>` — that is provably redundant with a
+ * DIFFERENT bold field `**<proofLabel>:** <value>` carrying the IDENTICAL value (Enhet 3b dedup
+ * primitive for the dual-**Dato:** mlops-genaiops file whose creation date equals its last-updated
+ * date). The sibling of dropRedundantPlainField, but across two distinct bold labels rather than a
+ * plain/bold pair. Refuses to guess: if no proof field exists, or the two values differ, it THROWS
+ * (that is a human decision — relabeling `**Dato:**`→`**Created:**` there would assert a creation
+ * date the file never truly had). No-op if the drop line is absent (idempotent). Operates in the
+ * header region only (`headerEndIndex`); body — including any `**<dropLabel>:**` template line — is
+ * byte-identical.
+ *
+ * @param {string} content — full existing file content
+ * @param {string} dropLabel — the label to remove, WITHOUT decoration, e.g. 'Dato'
+ * @param {string} proofLabel — the label whose identical value proves redundancy, e.g. 'Last updated'
+ * @returns {string} content with the redundant bold line removed, or unchanged
+ * @throws if either label is blank, no proof field proves redundancy, or the values differ
+ */
+export function dropRedundantBoldField(content, dropLabel, proofLabel) {
+  const s = String(content ?? '');
+  const dl = String(dropLabel ?? '').trim();
+  const pl = String(proofLabel ?? '').trim();
+  if (dl === '') throw new Error('dropRedundantBoldField: dropLabel is required');
+  if (pl === '') throw new Error('dropRedundantBoldField: proofLabel is required');
+  const escD = dl.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+  const escP = pl.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+  const dropRe = new RegExp('^\\s*\\*\\*' + escD + ':\\*\\*\\s*(\\S.*?)\\s*$', 'i');
+  const proofRe = new RegExp('^\\s*\\*\\*' + escP + ':\\*\\*\\s*(\\S.*?)\\s*$', 'i');
+
+  const lines = s.split('\n');
+  const end = headerEndIndex(lines);
+  let dropIdx = -1;
+  let dropVal = null;
+  let proofVal = null;
+  for (let i = 0; i < end; i++) {
+    const dm = dropRe.exec(lines[i]);
+    if (dm && dropIdx === -1) { dropIdx = i; dropVal = dm[1]; }
+    const pm = proofRe.exec(lines[i]);
+    if (pm && proofVal === null) proofVal = pm[1];
+  }
+  if (dropIdx === -1) return s; // nothing to drop (idempotent)
+  if (proofVal === null) throw new Error(`dropRedundantBoldField: no bold **${pl}:** to prove **${dl}:** '${dropVal}' redundant`);
+  if (proofVal !== dropVal) throw new Error(`dropRedundantBoldField: **${dl}:** '${dropVal}' ≠ **${pl}:** '${proofVal}' — not redundant, human decision`);
+  lines.splice(dropIdx, 1);
+  return lines.join('\n');
+}
+
 /**
  * Surgically insert-or-update ONLY the `**Verified:**` and `**Verified by:**` header lines
  * on an EXISTING KB file — the R7–R10 born-verified STAMP primitive. Unlike composeKbFile