a11y: The focus style of the suggested term is incorrect

[t-hamano]

Description

The suggested terms consist of two interactive elements: the Add and Dismiss buttons. It is difficult for keyboard users to discern which button has focus, as the focus styles are not sufficiently prominent.

Step-by-step reproduction instructions

• Open a post and enter the content.
• Click the "Suggest Categories" button.
• Focus on the terminal using the keyboard.

Screenshots, screen recording, code snippet

Add button is focused:

Dismiss button is focused:

Environment info

No response

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except the AI plugin.

• Yes

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure