feat(ms-ai-architect): Sesjon 19 — B3 merge-apply (cross-skill + taksonomi-persist) [skip-docs]

Merge-apply = den tyngste destruktive op-en: eksekver en operatør-godkjent
merge_skills-entry → faktisk cross-skill skills/-mutasjon. Tre mekanismer
som sanitize/retire ikke trengte: kuratert relokasjon (ikke arkiv),
taksonomi-persistering, retire-av-absorbert.

- taxonomy.mjs (ny persist): saveTaxonomy (atomisk .tmp+rename, speiler
  saveDecisions) + ren applyCategoryReassignments (repointer KUN der eier
  === from; absent/allerede-flyttet = no-op). Lag-0 er normalt read-only;
  ENESTE writer = gated merge-apply.
- applyApprovedAction merge-gren (skill-ops.mjs): re-plan fersk → revalidér
  (kollisjon → guardrail.ok=false → abort) → flytt absorbed-refs → absorber
  (moveFile; flyttingen ER bevaringen set-equality beviser) → persister
  taksonomi-repoint fra FERSK plan (drift-sikker) → arkivér absorbed-SKILL.md
  FØR rmdir → flipp ledger approved→applied. Description-forsoning forblir
  MANUELL (planner-kontrakt: apply rører aldri absorber-SKILL.md).
  archiveMove→moveFile (generisk: arkiv + kuratert flytt).
- CLI apply-skill-op.mjs merge <absorber> <absorbed> — lookup via actionKey
  (merge_skills:<sortert par>); default PREVIEW, --apply = dobbel-gate.

TDD, tmpdir-fixtures: 0 ekte skills/-mutasjon. Ny test-skill-ops-merge-apply
(7) + 2 taksonomi-tester; fjernet foreldet merge-throws fra S18-fila. Tester:
kb-eval 78→84, kb-update 137→139; validate 239 · kb-integrity 192/192 uendret.
eval --json deterministisk uendret (K10 eng+infra FAIL, øvrige PASS).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/kb-eval/test-skill-ops-apply.test.mjs

@@ -1,9 +1,9 @@
 // tests/kb-eval/test-skill-ops-apply.test.mjs
 // Spor B / B3 (Sesjon 18): the APPLY-PATH — the destructive frontier. An
 // operator-approved (status:approved) ledger entry is executed into a real
-// skills/ mutation. Single-skill ops only this session (sanitize + retire);
-// merge-apply is staged to S19 (it needs taxonomy persistence + cross-skill
-// moves). create_skill comes last.
+// skills/ mutation. This file covers the SINGLE-SKILL ops (sanitize + retire);
+// merge-apply (cross-skill, Sesjon 19) lives in test-skill-ops-merge-apply.test.mjs;
+// create_skill comes last.
 //
 // Binding contract proven here:
 //   1. revalidateApply (pure) re-checks an approved entry against a FRESH plan:
@@ -30,7 +30,6 @@ import {
   planSanitizeSkill,
   SANITIZE_OPERATION,
   RETIRE_OPERATION,
-  MERGE_OPERATION,
 } from '../../scripts/kb-eval/lib/skill-ops.mjs';
 import {
   loadDecisions,
@@ -269,18 +268,3 @@ test('applyApprovedAction — a guardrail-failing approved entry never applies',
     assert.ok(existsSync(join(skillsDir, 'skill-a/references/cat1/live.md')), 'curated ref still safe');
   });
 });
-
-test('applyApprovedAction — merge_skills is unsupported this session (staged to S19) and throws', () => {
-  withFixture(({ root, skillsDir, agentsDir, dataDir }) => {
-    const approved = {
-      operation_type: MERGE_OPERATION,
-      status: 'approved',
-      targets: { absorber: 'skill-a', absorbed: 'skill-b' },
-      guardrail: { ok: true },
-    };
-    assert.throws(
-      () => applyApprovedAction(approved, { pluginRoot: root, skillsDir, agentsDir, dataDir, apply: true }),
-      /merge|unsupported|S19/i,
-    );
-  });
-});