test: add MVP QA gate

src/lib/testing/external-api-mocks.test.ts

@@ -0,0 +1,13 @@
+import { describe, expect, test } from "vitest";
+import { externalApiHandlers } from "./external-api-mocks";
+
+describe("external API mocks", () => {
+  test("defines deterministic handlers for deferred datasource adapters", () => {
+    expect(externalApiHandlers).toHaveLength(3);
+    expect(externalApiHandlers.map((handler) => handler.info.header)).toEqual([
+      "GET https://prometheus.dimensionlab.net/api/v1/query",
+      "GET https://uptime.dimensionlab.net/api/status-page/*",
+      "GET https://api.open-meteo.com/v1/forecast",
+    ]);
+  });
+});