fix(payments-cart): update cart taxAddress type

Because:

- The cart was returning the incorrect type for taxaddress

This commit:

- Modifies the kysely-types entry in accordance with the example here:
https://kysely.dev/docs/getting-started#types

Closes FXA-10172

libs/payments/cart/src/lib/cart.factories.ts

@@ -83,7 +83,7 @@ export const ResultCartFactory = (
   offeringConfigId: faker.string.uuid(),
   interval: faker.string.numeric(),
   experiment: null,
-  taxAddress: JSON.stringify(TaxAddressFactory()),
+  taxAddress: TaxAddressFactory(),
   createdAt: faker.date.past().getTime(),
   updatedAt: faker.date.past().getTime(),
   couponCode: null,

libs/payments/cart/src/lib/cart.service.ts

@@ -13,7 +13,6 @@ import {
   InvoiceManager,
   StripeCustomer,
   SubplatInterval,
-  TaxAddress,
 } from '@fxa/payments/stripe';
 import { CartErrorReasonId, CartState } from '@fxa/shared/db/mysql/account';
 import { GeoDBManager } from '@fxa/shared/geodb';
@@ -124,7 +123,7 @@ export class CartService {
       interval: oldCart.interval,
       offeringConfigId: oldCart.offeringConfigId,
       experiment: oldCart.experiment || undefined,
-      taxAddress: (oldCart.taxAddress as unknown as TaxAddress) || undefined, // TODO: Fix the typings for taxAddress
+      taxAddress: oldCart.taxAddress || undefined,
       couponCode: oldCart.couponCode || undefined,
       stripeCustomerId: oldCart.stripeCustomerId || undefined,
       email: oldCart.email || undefined,
@@ -233,7 +232,7 @@ export class CartService {
     const invoicePreview = await this.invoiceManager.preview({
       priceId,
       customer,
-      taxAddress: cart.taxAddress as unknown as TaxAddress, // TODO: Fix the typings for taxAddress
+      taxAddress: cart.taxAddress || undefined,
     });
 
     return {

libs/shared/db/mysql/account/src/lib/kysely-types.ts

@@ -4,7 +4,7 @@
 /**
  * This file is generated by kysely-codegen. Merge edits as needed.
  */
-import type { ColumnType } from 'kysely';
+import type { ColumnType, JSONColumnType } from 'kysely';
 
 export type Generated<T> = T extends ColumnType<infer S, infer I, infer U>
   ? ColumnType<S, I | undefined, U>
@@ -91,7 +91,10 @@ export interface Carts {
   offeringConfigId: string;
   interval: string;
   experiment: string | null;
-  taxAddress: Json | null;
+  taxAddress: JSONColumnType<{
+    countryCode: string;
+    postalCode: string;
+  }> | null;
   createdAt: number;
   updatedAt: number;
   couponCode: string | null;