Docs: add config drift baseline statefile (#45891)

* Docs: add config drift statefile generator

* Docs: generate config drift baseline

* CI: move config docs drift runner into workflow sanity

* Docs: emit config drift baseline json

* Docs: commit config drift baseline json

* Docs: wire config baseline into release checks

* Config: fix baseline drift walker coverage

* Docs: regenerate config drift baselines

scripts/generate-config-doc-baseline.ts

@@ -0,0 +1,44 @@
+#!/usr/bin/env node
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import { writeConfigDocBaselineStatefile } from "../src/config/doc-baseline.js";
+
+const args = new Set(process.argv.slice(2));
+const checkOnly = args.has("--check");
+
+if (checkOnly && args.has("--write")) {
+  console.error("Use either --check or --write, not both.");
+  process.exit(1);
+}
+
+const repoRoot = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..");
+const result = await writeConfigDocBaselineStatefile({
+  repoRoot,
+  check: checkOnly,
+});
+
+if (checkOnly) {
+  if (!result.changed) {
+    console.log(
+      `OK ${path.relative(repoRoot, result.jsonPath)} ${path.relative(repoRoot, result.statefilePath)}`,
+    );
+    process.exit(0);
+  }
+  console.error(
+    [
+      "Config baseline drift detected.",
+      `Expected current: ${path.relative(repoRoot, result.jsonPath)}`,
+      `Expected current: ${path.relative(repoRoot, result.statefilePath)}`,
+      "If this config-surface change is intentional, run `pnpm config:docs:gen` and commit the updated baseline files.",
+      "If not intentional, treat this as docs drift or a possible breaking config change and fix the schema/help changes first.",
+    ].join("\n"),
+  );
+  process.exit(1);
+}
+
+console.log(
+  [
+    `Wrote ${path.relative(repoRoot, result.jsonPath)}`,
+    `Wrote ${path.relative(repoRoot, result.statefilePath)}`,
+  ].join("\n"),
+);