feat: story library, player and builder UI

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/app.test.tsx

@@ -26,26 +26,44 @@ afterEach(() => {
 });
 
 describe("app", () => {
-  it("home shows the app name from runtime config and the build sha", async () => {
+  it("library lists published stories and links to play", async () => {
+    vi.stubGlobal(
+      "fetch",
+      vi.fn(
+        async () =>
+          new Response(
+            JSON.stringify({
+              stories: [
+                {
+                  id: "s1",
+                  title: "Cave",
+                  description: "Dark",
+                  nodeCount: 3,
+                  published: true,
+                },
+              ],
+            }),
+          ),
+      ),
+    );
     renderAt("/");
     expect(
-      await screen.findByRole("heading", { name: "test-app" }),
+      await screen.findByRole("heading", { name: "Cave" }),
     ).toBeInTheDocument();
-    expect(screen.getByTestId("build-sha")).toHaveTextContent("dev");
+    expect(
+      screen.getAllByRole("link", { name: "Play" }).at(-1)!,
+    ).toHaveAttribute("href", "/play/s1");
   });
 
-  it("home hides the banner while hello-banner is off", async () => {
-    renderAt("/");
-    await screen.findByRole("heading", { name: "test-app" });
-    expect(screen.queryByTestId("banner")).not.toBeInTheDocument();
-  });
-
-  it("home shows the banner while hello-banner is on", async () => {
-    flagsOn.add("hello-banner");
-    renderAt("/");
-    expect(await screen.findByTestId("banner")).toHaveTextContent(
-      "hello-banner flag is on",
+  it("library shows a builder prompt when empty", async () => {
+    vi.stubGlobal(
+      "fetch",
+      vi.fn(async () => new Response(JSON.stringify({ stories: [] }))),
     );
+    renderAt("/");
+    expect(
+      await screen.findByText(/No published stories yet/),
+    ).toBeInTheDocument();
   });
 
   it("status fetches / and /readyz under API_BASE_URL and renders the JSON", async () => {