Automatically prepare the bundled Navidrome sidecar and replace demo content with real-library scan states and polling

Hop-State: A_06FNEE4FJ502PSGDYQ3272G
Hop-Proposal: R_06FNED6AR1ZZM7CJH7ETC9G
Hop-Task: T_06FNEAPFW0DYEP35V3BMAHG
Hop-Attempt: AT_06FNEAPFW1QY3KAF1QM61N0

src/lib/librarySync.test.ts

@@ -0,0 +1,27 @@
+import { describe, expect, it, vi } from "vitest";
+import { pollForLibrary } from "./librarySync";
+
+describe("pollForLibrary", () => {
+  it("waits until Navidrome returns indexed tracks", async () => {
+    const load = vi.fn()
+      .mockRejectedValueOnce(new Error("server is still starting"))
+      .mockResolvedValueOnce({ tracks: [] })
+      .mockResolvedValueOnce({ tracks: [] })
+      .mockResolvedValueOnce({ tracks: [{ id: "real-track" }] });
+    const wait = vi.fn().mockResolvedValue(undefined);
+
+    await expect(pollForLibrary(load, { attempts: 5, wait })).resolves.toEqual({
+      tracks: [{ id: "real-track" }],
+    });
+    expect(load).toHaveBeenCalledTimes(4);
+    expect(wait).toHaveBeenCalledTimes(3);
+  });
+
+  it("returns null when the scan never yields a track", async () => {
+    const load = vi.fn().mockResolvedValue({ tracks: [] });
+    const wait = vi.fn().mockResolvedValue(undefined);
+
+    await expect(pollForLibrary(load, { attempts: 3, wait })).resolves.toBeNull();
+    expect(load).toHaveBeenCalledTimes(3);
+  });
+});