feat(tip): add coffee tipping page

src/app/tip/tip-screen.helpers.ts

@@ -0,0 +1,33 @@
+import type { LoginStatus } from "@/data/dto/auth";
+import type { PaymentPlan } from "@/data/dto/payment";
+
+const TIP_COFFEE_PLAN_ID = "tip_coffee";
+const TIP_COFFEE_ORDER_TYPE = "tip_coffee";
+
+export function findTipCoffeePlan(
+  plans: readonly PaymentPlan[],
+): PaymentPlan | null {
+  return (
+    plans.find((plan) => plan.planId === TIP_COFFEE_PLAN_ID) ??
+    plans.find((plan) => plan.orderType === TIP_COFFEE_ORDER_TYPE) ??
+    null
+  );
+}
+
+export function formatTipPrice(plan: PaymentPlan | null): string {
+  if (!plan) return "US$ 5";
+
+  const amount = plan.amountCents / 100;
+  const formattedAmount = Number.isInteger(amount)
+    ? String(amount)
+    : amount.toFixed(2).replace(/\.?0+$/, "");
+  const currency = plan.currency.trim().toUpperCase();
+
+  if (currency === "USD") return `US$ ${formattedAmount}`;
+  if (currency.length > 0) return `${currency} ${formattedAmount}`;
+  return formattedAmount;
+}
+
+export function isRealLoginStatus(loginStatus: LoginStatus): boolean {
+  return loginStatus !== "notLoggedIn" && loginStatus !== "guest";
+}