docs(site): [SITE-01] inventory sources and reconcile demo coverage

refactor/scripts/site-inventory.test.mjs

@@ -0,0 +1,19 @@
+import assert from 'node:assert/strict'
+// eslint-disable-next-line test/no-import-node-test -- Runs with the repository baseline node:test suite.
+import test from 'node:test'
+import { captureSiteInventory, validateSiteInventory } from './site-inventory.mjs'
+
+test('Site inventory detects omitted HTML, declarations and fingerprint drift', () => {
+  const snapshot = captureSiteInventory()
+  validateSiteInventory(snapshot)
+  for (const mutate of [
+    value => value.pages = value.pages.filter(page => page.source !== 'docs/mobile.html'),
+    value => value.editorDeclarations.pop(),
+    value => value.assets[0].sha256 = 'changed',
+    value => value.api.pop(),
+  ]) {
+    const changed = structuredClone(snapshot)
+    mutate(changed)
+    assert.throws(() => validateSiteInventory(changed))
+  }
+})