Add processing for additional error codes in chat

What does this MR do and why?

with feat: don't process unsupported tools (gitlab-org/modelops/applied-ml/code-suggestions/ai-assist!1514 - merged) Duo Chat agent will return additional error codes that we need to show to users

Add processing for additional error codes

Changelog: added EE: true

References

https://gitlab.com/gitlab-org/modelops/applied-ml/code-suggestions/ai-assist/-/issues/686+

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