feat: add lazyWithRetry for chunk load failure recovery

tests/unit/web/lazy-with-retry.test.ts

@@ -0,0 +1,42 @@
+// @vitest-environment jsdom
+import { describe, expect, it, vi } from "vitest";
+
+import { retryDynamicImport } from "@/lib/lazy-with-retry";
+
+describe("retryDynamicImport", () => {
+  it("resolves on first success", async () => {
+    const mod = { default: () => null };
+    const importFn = vi.fn().mockResolvedValue(mod);
+    const result = await retryDynamicImport(importFn);
+    expect(result).toBe(mod);
+    expect(importFn).toHaveBeenCalledTimes(1);
+  });
+
+  it("retries on failure and resolves on eventual success", async () => {
+    const mod = { default: () => null };
+    const importFn = vi
+      .fn()
+      .mockRejectedValueOnce(new TypeError("Failed to fetch dynamically imported module"))
+      .mockRejectedValueOnce(new TypeError("Failed to fetch dynamically imported module"))
+      .mockResolvedValue(mod);
+    const result = await retryDynamicImport(importFn, 3, 0);
+    expect(result).toBe(mod);
+    expect(importFn).toHaveBeenCalledTimes(3);
+  });
+
+  it("rejects after all retries exhausted", async () => {
+    const err = new TypeError("Failed to fetch dynamically imported module");
+    const importFn = vi.fn().mockRejectedValue(err);
+    await expect(retryDynamicImport(importFn, 3, 0)).rejects.toThrow(
+      "Failed to fetch dynamically imported module",
+    );
+    expect(importFn).toHaveBeenCalledTimes(3);
+  });
+
+  it("only retries chunk-related errors, not other errors", async () => {
+    const err = new Error("Some other error");
+    const importFn = vi.fn().mockRejectedValue(err);
+    await expect(retryDynamicImport(importFn, 3, 0)).rejects.toThrow("Some other error");
+    expect(importFn).toHaveBeenCalledTimes(1);
+  });
+});