fix: add modal type to subscriptionEligibility (#7124)

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Add missing modalType field and constant to SubscriptionEligibility

## References

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## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [x] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds optional `modalType` to `SubscriptionEligibility`, introduces
`MODAL_TYPE/ModalType`, and updates exports and tests.
> 
> - **Types**:
>   - Add `MODAL_TYPE` constant and `ModalType` type in `src/types.ts`.
>   - Extend `SubscriptionEligibility` with optional `modalType` field.
> - **Exports**:
>   - Export `ModalType` and `MODAL_TYPE` from `src/index.ts`.
> - **Tests**:
> - Update `SubscriptionController.test.ts` to import `MODAL_TYPE` and
include `modalType` in eligibility mocks.
> - **Changelog**:
> - Document addition of `modalType` field and constant in
`CHANGELOG.md`.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
612be7c. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: tuna1207

packages/subscription-controller/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Added `modalType` field and constant to `SubscriptionEligibility` ([#7124](https://github.com/MetaMask/core/pull/7124))
+
 ## [4.0.0]
 
 ### Added

packages/subscription-controller/src/SubscriptionController.test.ts

@@ -42,6 +42,7 @@ import type {
   RecurringInterval,
 } from './types';
 import {
+  MODAL_TYPE,
   PAYMENT_TYPES,
   PRODUCT_TYPES,
   RECURRING_INTERVALS,
@@ -1426,6 +1427,7 @@ describe('SubscriptionController', () => {
       canSubscribe: true,
       minBalanceUSD: 100,
       canViewEntryModal: true,
+      modalType: MODAL_TYPE.A,
       cohorts: [],
       assignedCohort: null,
       hasAssignedCohortExpired: false,

packages/subscription-controller/src/index.ts

@@ -65,6 +65,7 @@ export type {
   BalanceCategory,
   AssignCohortRequest,
   GetSubscriptionsEligibilitiesRequest,
+  ModalType,
 } from './types';
 export {
   CRYPTO_PAYMENT_METHOD_ERRORS,
@@ -75,6 +76,7 @@ export {
   SubscriptionUserEvent,
   COHORT_NAMES,
   BALANCE_CATEGORIES,
+  MODAL_TYPE,
 } from './types';
 export { SubscriptionServiceError } from './errors';
 export { Env, SubscriptionControllerErrorMessage } from './constants';

packages/subscription-controller/src/types.ts

@@ -53,6 +53,13 @@ export const CRYPTO_PAYMENT_METHOD_ERRORS = {
 export type CryptoPaymentMethodError =
   (typeof CRYPTO_PAYMENT_METHOD_ERRORS)[keyof typeof CRYPTO_PAYMENT_METHOD_ERRORS];
 
+export const MODAL_TYPE = {
+  A: 'A',
+  B: 'B',
+} as const;
+
+export type ModalType = (typeof MODAL_TYPE)[keyof typeof MODAL_TYPE];
+
 /** only usd for now */
 export type Currency = 'usd';
 
@@ -266,6 +273,7 @@ export type SubscriptionEligibility = {
   canSubscribe: boolean;
   minBalanceUSD: number;
   canViewEntryModal: boolean;
+  modalType?: ModalType;
   cohorts: Cohort[];
   assignedCohort: string | null;
   hasAssignedCohortExpired: boolean;