chore: import upstream snapshot with attribution

showcase/scripts/verify-deploy.drivers.eval.ts

@@ -0,0 +1,25 @@
+import type { ProbeTarget } from "./verify-deploy";
+import type { ProbeOutcome } from "./verify-deploy.drivers";
+import { probeBaseline } from "./verify-deploy.drivers.baseline";
+
+/**
+ * Feature-level verifier for `showcase-eval`.
+ *
+ * No SSOT entry currently sets `probe.driver === "eval"` (eval has not
+ * been wired into the SSOT yet), but the enum literal exists in
+ * `railway-envs.ts::ProbeDriver` and the dispatch switch in
+ * `verify-deploy.drivers.ts` routes to this function. Per the
+ * cross-workstream contract (the 10-literal enum is the surface), every
+ * literal must have a working baseline impl — so this is NOT a stub.
+ *
+ * Baseline (this commit): Railway deployment-SUCCESS + HTTP 200 on
+ * `/api/health` (the standard Next.js/Express health path used by every
+ * other API-shaped service in the SSOT). Future driver-specific layer:
+ * synthetic eval-run fixture call.
+ */
+export async function probeEval(target: ProbeTarget): Promise<ProbeOutcome> {
+  return probeBaseline(target, {
+    driverLabel: "eval",
+    healthcheckPath: "/api/health",
+  });
+}