fix: Isuserrejected error when cause exists but undefined (#10666)

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---

## PR-Codex overview
This PR updates error handling logic in `sentry.ts` and
`sentry.client.config.js` to check for the existence of `err.cause`
before accessing its properties.

### Detailed summary
- Updated error handling logic to check for `err.cause` existence before
accessing its properties.

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question}`

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apps/web/sentry.client.config.js

@@ -22,7 +22,7 @@ const isUserRejected = (err) => {
   if (err && typeof err === 'object') {
     if (
       ('code' in err && (err.code === 4001 || err.code === 'ACTION_REJECTED')) ||
-      ('cause' in err && 'code' in err.cause && err.cause.code === 4001)
+      ('cause' in err && err.cause && 'code' in err.cause && err.cause.code === 4001)
     ) {
       return true
     }

apps/web/src/utils/sentry.ts

@@ -36,7 +36,7 @@ export const isUserRejected = (err) => {
   if (err && typeof err === 'object') {
     if (
       ('code' in err && (err.code === 4001 || err.code === 'ACTION_REJECTED')) ||
-      ('cause' in err && 'code' in err.cause && err.cause.code === 4001)
+      ('cause' in err && err.cause && 'code' in err.cause && err.cause.code === 4001)
     ) {
       return true
     }