test(refactor): [BASE-01] freeze published core and chapter baselines

refactor/scripts/releases.test.mjs

@@ -0,0 +1,11 @@
+import assert from 'node:assert/strict'
+import { test } from 'node:test'
+import { hash, verifyIntegrity } from './releases.mjs'
+
+test('release integrity rejects corrupted bytes and inconsistent frozen digests', () => {
+  const bytes = Buffer.from('known release artifact')
+  const release = { name: 'fixture', integrity: `sha512-${hash(bytes, 'sha512', 'base64')}`, sha256: hash(bytes) }
+  assert.doesNotThrow(() => verifyIntegrity(bytes, release))
+  assert.throws(() => verifyIntegrity(Buffer.from('replaced artifact'), release), /Integrity mismatch/)
+  assert.throws(() => verifyIntegrity(bytes, { ...release, sha256: '0'.repeat(64) }), /Archive hash mismatch/)
+})