fix: Copy attributes to have different copies in different threads.

[denischilik]

Background

Copy attributes to have different copies in different threads.

We identified a crash caused by a race condition between the background message queue (performing JSON serialization) and the main thread (triggered via MPListenerController).

The issue occurred because the same mutable NSDictionary instance was accessed concurrently from different threads.

What Has Changed

Added [attributes copy] in MPIntegrationAttributes initializer to always store an immutable snapshot of attributes, and created an additional copy in setIntegrationAttributes:forKit: so the listener (main thread) and message queue (background thread) each work with their own independent copies.

Screenshots/Video

• {Include any screenshots or video demonstrating the new feature or fix, if applicable}

Checklist

• I have performed a self-review of my own code.
• I have made corresponding changes to the documentation.
• I have added tests that prove my fix is effective or that my feature works.
• I have tested this locally.

Additional Notes

• {Any additional information or context relevant to this PR}

Reference Issue (For employees only. Ignore if you are an outside contributor)

• Closes https://rokt.atlassian.net/browse/SDKE-360

[nickolas-dimitrakas]

LGTM

[mparticle-automation]

🎉 This PR is included in version 8.40.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀