fix: trigger access token refresh (#7149)

## Explanation

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- Previously `triggerAccessTokenRefresh` was only called during
`getSubscriptions` polling, normal subscription state change didn't
trigger it.
This PR trigger `triggerAccessTokenRefresh` everytime subscription state
change
- Remove `triggerAccessTokenRefresh` from
`startShieldSubscriptionWithCard` since that only return stripe checkout
url, not subscribed yet.

## 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]
> Refresh access token immediately when subscription state changes and
remove refresh after starting card/crypto checkout; delete polling
flag/logic.
> 
> - **Subscription Controller**:
> - **Behavior**: Call `triggerAccessTokenRefresh` in `getSubscriptions`
whenever state changes (subscriptions/customer/trials/lastSubscription).
> - **Refactor**: Remove `#shouldCallRefreshAuthToken` and related
polling conditional; `_executePoll` now only calls `getSubscriptions`.
> - **Flows**: Remove `triggerAccessTokenRefresh` after
`startShieldSubscriptionWithCard` and `startSubscriptionWithCrypto`
(checkout/session creation only).
> - **Docs**:
> - Update `CHANGELOG.md` to reflect the new refresh behavior and
removal after card checkout.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
04b3ce9. 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 +7,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- Trigger `triggerAccessTokenRefresh` everytime subscription state change instead of only when polling ([#7149](https://github.com/MetaMask/core/pull/7149))
+- Remove `triggerAccessTokenRefresh` after `startShieldSubscriptionWithCard` ([#7149](https://github.com/MetaMask/core/pull/7149))
+
 ## [4.2.1]
 
 ### Added

packages/subscription-controller/src/SubscriptionController.ts

@@ -241,8 +241,6 @@ export class SubscriptionController extends StaticIntervalPollingController()<
 > {
   readonly #subscriptionService: ISubscriptionService;
 
-  #shouldCallRefreshAuthToken: boolean = false;
-
   /**
    * Creates a new SubscriptionController instance.
    *
@@ -391,7 +389,8 @@ export class SubscriptionController extends StaticIntervalPollingController()<
         state.trialedProducts = newTrialedProducts;
         state.lastSubscription = newLastSubscription;
       });
-      this.#shouldCallRefreshAuthToken = true;
+      // trigger access token refresh to ensure the user has the latest access token if subscription state change
+      this.triggerAccessTokenRefresh();
     }
 
     return newSubscriptions;
@@ -466,8 +465,7 @@ export class SubscriptionController extends StaticIntervalPollingController()<
 
     const response =
       await this.#subscriptionService.startSubscriptionWithCard(request);
-
-    this.triggerAccessTokenRefresh();
+    // note: no need to trigger access token refresh after startSubscriptionWithCard request because this only return stripe checkout session url, subscription not created yet
 
     return response;
   }
@@ -476,7 +474,7 @@ export class SubscriptionController extends StaticIntervalPollingController()<
     this.#assertIsUserNotSubscribed({ products: request.products });
     const response =
       await this.#subscriptionService.startSubscriptionWithCrypto(request);
-    this.triggerAccessTokenRefresh();
+
     return response;
   }
 
@@ -730,10 +728,6 @@ export class SubscriptionController extends StaticIntervalPollingController()<
 
   async _executePoll(): Promise<void> {
     await this.getSubscriptions();
-    if (this.#shouldCallRefreshAuthToken) {
-      this.triggerAccessTokenRefresh();
-      this.#shouldCallRefreshAuthToken = false;
-    }
   }
 
   /**