test: establish frontend gate taxonomy

tests/integration/http-boundary.test.js

@@ -0,0 +1,23 @@
+import { HttpResponse, http } from "msw";
+import { setupServer } from "msw/node";
+import { afterAll, afterEach, beforeAll, describe, expect, it } from "vitest";
+
+const server = setupServer(
+  http.get("https://example.test/health", () =>
+    HttpResponse.json({ success: true, data: { status: "ok" } }),
+  ),
+);
+
+beforeAll(() => server.listen({ onUnhandledRequest: "error" }));
+afterEach(() => server.resetHandlers());
+afterAll(() => server.close());
+
+describe("integration test level", () => {
+  it("uses MSW to isolate the HTTP boundary", async () => {
+    const response = await fetch("https://example.test/health");
+    await expect(response.json()).resolves.toEqual({
+      success: true,
+      data: { status: "ok" },
+    });
+  });
+});