feat(analytics): add behavior and payment funnel tracking

src/lib/payment/__tests__/payment_launch.test.ts

@@ -1,9 +1,10 @@
-import { describe, expect, it } from "vitest";
+import { describe, expect, it, vi } from "vitest";
 
 import {
   getPaymentUrl,
   getStripeClientSecret,
   isEzpayPayment,
+  launchEzpayRedirect,
 } from "../payment_launch";
 
 describe("payment launch helpers", () => {
@@ -40,4 +41,22 @@ describe("payment launch helpers", () => {
       }),
     ).toBeNull();
   });
+
+  it("reports a launch failure before redirecting without an order id", async () => {
+    const onOpened = vi.fn();
+    const onFailed = vi.fn();
+
+    await launchEzpayRedirect({
+      orderId: null,
+      paymentUrl: "https://pay.example/checkout?token=secret",
+      subscriptionType: "topup",
+      onOpened,
+      onFailed,
+    });
+
+    expect(onOpened).not.toHaveBeenCalled();
+    expect(onFailed).toHaveBeenCalledWith(
+      "Missing order id before opening Ezpay.",
+    );
+  });
 });