Improve toast accessibility live region

[JLG-WOCFR-DEV]

Summary

• initialize the toast live region with the appropriate ARIA role and politeness handling while keeping notifications in place
• tweak toast container styling so it stays visually consistent without capturing pointer focus
• extend the import configuration manual test to confirm the toast container and items expose the required accessibility attributes

Testing

• not run (not requested)

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https://chatgpt.com/codex/tasks/task_e_68dd2020b66c832eb5ab4f90c88d56f2