LIVE-20867: prevent infinite rendering cycles when purging anonymous notifications

[marcotoniut-ledger]

✅ Checklist

• npx changeset was attached.
• Covered by automatic tests.
• Impact of the changes:
  • Some changes in how anonymous notifications are purged when tracking stops.
  • Prevents unnecessary renders and API calls.
  • Reduces CPU usage and resolves the infinite loop.
  • Keeps purge behaviour intact for stale notifications.

📝 Description

This PR addresses an infinite loop issue observed in PROD-11430, where CLEAR_DISMISSED_CONTENT_CARDS and updateAnonymousUserNotifications were repeatedly dispatched, causing extreme CPU usage and UI lag.

The issue occurs for untracked users when anonymousUserNotifications contains a mix of expired and valid entries during initialisation. The purge logic in useBraze partially removes expired items but still generates a new object reference on every run. Because this updated object is part of the initBraze dependency array, it continuously re-triggers initBraze, causing repeated Braze re-initialisations and excessive API calls.

Fix:

• Updated purge logic to only create a new anonymousUserNotifications object when changes are detected.
• Ensured cleanup converges to a stable state after the first pass to prevent repeated triggers.
• Maintained existing behaviour for tracked users and normal content card updates.

❓ Context

• JIRA: LIVE-20867

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🧐 Checklist for the PR Reviewers

• The code aligns with the requirements described in the linked JIRA or GitHub issue.
• The PR description clearly documents the changes made and explains any technical trade-offs or design decisions.
• There are no undocumented trade-offs, technical debt, or maintainability issues.
• The PR has been tested thoroughly, and any potential edge cases have been considered and handled.
• Any new dependencies have been justified and documented.
• Performance considerations have been taken into account. (changes have been profiled or benchmarked if necessary)

[vercel]

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Project	Deployment	Preview	Comments	Updated (UTC)
web-tools	❌ Failed			Aug 13, 2025 9:01am

3 Skipped Deployments

Project	Deployment	Preview	Comments	Updated (UTC)
ledger-live-github-bot	⬜️ Ignored	Preview		Aug 13, 2025 9:01am
native-ui-storybook	⬜️ Ignored	Preview		Aug 13, 2025 9:01am
react-ui-storybook	⬜️ Ignored	Preview		Aug 13, 2025 9:01am

[sonarqubecloud]

Quality Gate failed

Failed conditions
43.2% Coverage on New Code (required ≥ 80%)
C Reliability Rating on New Code (required ≥ A)
4 New Code Smells (required ≤ 1)

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[sentry-io]

Suspect Issues

This pull request was deployed and Sentry observed the following issues:

• ‼️ TypeError: y.set is not a function in production

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