chore: remove 'minBalanceUSD' from eligibility response (#7248)

## Explanation

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This PR removes `minBalanceUSD` from eligibility response.
## 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)
- [x] I've introduced [breaking
changes](https://github.com/MetaMask/core/tree/main/docs/breaking-changes.md)
in this PR and have prepared draft pull requests for clients and
consumer packages to resolve them

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Remove `minBalanceUSD` from subscription eligibility and update
related tests/mocks.
> 
> - **Types**:
> - Remove `minBalanceUSD` from `SubscriptionEligibility` in
`packages/subscription-controller/src/types.ts`.
> - **Tests**:
> - Update mocks and expectations in
`packages/subscription-controller/src/SubscriptionController.test.ts`
and `packages/subscription-controller/src/SubscriptionService.test.ts`
to drop `minBalanceUSD` from eligibility payloads and defaults.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
53c0a5c. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

Author: lwin-kyaw

packages/subscription-controller/CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- Removed `minBalanceUSD` field from the `SubscriptionEligibility` type. ([#7248](https://github.com/MetaMask/core/pull/7248))
 - Updated `submitShieldSubscriptionCryptoApproval` to handle change payment method transaction if subscription already existed ([#7231](https://github.com/MetaMask/core/pull/7231))
 - Bump `@metamask/transaction-controller` from `^62.0.0` to `^62.3.0` ([#7215](https://github.com/MetaMask/core/pull/7215), [#7220](https://github.com/MetaMask/core/pull/7220), [#7236](https://github.com/MetaMask/core/pull/7236))
 - Move peer dependencies for controller and service packages to direct dependencies ([#7209](https://github.com/MetaMask/core/pull/7209))

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

@@ -1425,7 +1425,6 @@ describe('SubscriptionController', () => {
     const MOCK_SUBSCRIPTION_ELIGIBILITY: SubscriptionEligibility = {
       product: PRODUCT_TYPES.SHIELD,
       canSubscribe: true,
-      minBalanceUSD: 100,
       canViewEntryModal: true,
       modalType: MODAL_TYPE.A,
       cohorts: [],

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

@@ -98,7 +98,6 @@ function createMockEligibilityResponse(overrides = {}) {
   return {
     product: PRODUCT_TYPES.SHIELD,
     canSubscribe: true,
-    minBalanceUSD: 100,
     canViewEntryModal: true,
     cohorts: [],
     assignedCohort: null,
@@ -474,7 +473,6 @@ describe('SubscriptionService', () => {
         handleFetchMock.mockResolvedValue([
           {
             product: PRODUCT_TYPES.SHIELD,
-            minBalanceUSD: 100,
           },
         ]);
 

packages/subscription-controller/src/types.ts

@@ -273,7 +273,6 @@ export type Cohort = {
 export type SubscriptionEligibility = {
   product: ProductType;
   canSubscribe: boolean;
-  minBalanceUSD: number;
   canViewEntryModal: boolean;
   modalType?: ModalType;
   cohorts: Cohort[];