agent_ui: Allow "token reached" callout to be dismissed (#45595)

It was previously impossible to dismiss the "token usage
reaching/reached the limit" callout.

<img width="500" height="392" alt="Screenshot 2025-12-23 at 5  49@2x"
src="https://github.com/user-attachments/assets/7fd8b126-dd3f-430b-9fea-ca05c73e5643"
/>

Release Notes:

- N/A
a34fe06bb1Danilo Leal committed on 12/23/2025, 9:14:58 PM· committed by GitHubparent0ce484e
1 file changedLine totals unavailable