Fix AI tabs transitionend listener not being removed after leaving fullscreen.

[l-lejman]

🚀 Summary

Adding and removing event listeners used different function references, so the listeners were not removed properly. We need to use a wrapper function or store the .bind(this) reference to properly remove the listeners.

The issue can be reproduced by simply opening and closing fullscreen mode, then using maximize in AI Chat.

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📌 Related issues

• Closes Fullscreen causes AI resize to throw console errors #20129

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💡 Additional information

Optional: Notes on decisions, edge cases, or anything helpful for reviewers.

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