feat(payment): implement coffee tip plans and update payment flow

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

@@ -29,24 +29,23 @@ function makePlan(input: Partial<PaymentPlanInput>): PaymentPlan {
 }
 
 describe("tip screen helpers", () => {
-  it("uses the legacy tip coffee plan only for small", () => {
+  it("matches the official small coffee plan", () => {
     const plan = makePlan({
-      planId: "tip_coffee",
+      planId: "tip_coffee_usd_4_99",
     });
 
     expect(findTipCoffeePlan([makePlan({}), plan], "small")).toBe(plan);
-    expect(findTipCoffeePlan([plan], "medium")).toBeNull();
   });
 
   it("matches medium and large coffee plans independently", () => {
     const medium = makePlan({
-      planId: "tip_coffee_medium",
-      orderType: "tip_coffee_medium",
+      planId: "tip_coffee_usd_9_99",
+      orderType: "tip",
       amountCents: 999,
     });
     const large = makePlan({
-      planId: "tip_coffee_large",
-      orderType: "tip_coffee_large",
+      planId: "tip_coffee_usd_19_99",
+      orderType: "tip",
       amountCents: 1999,
     });
 
@@ -57,7 +56,7 @@ describe("tip screen helpers", () => {
   it("does not infer a coffee tier from order type or amount", () => {
     const ambiguousPlan = makePlan({
       planId: "legacy_coffee",
-      orderType: "tip_coffee_medium",
+      orderType: "tip",
       amountCents: 999,
     });