[serverless] Attack Discovery UI updates

[benironside]

Part of #5889 — updates screenshots for Attack Discovery as well as references to the number of alerts it can process and the default alerts that get sent to the LLM.

Preview: Go to the link in this comment then go to Security -> View serverless docs -> AI for security -> Attack Discovery

[github-actions]

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[mergify]

This pull request does not have a backport label. Could you fix it @benironside? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• v7.x is the label to automatically backport to the 7.x branch.
• v7./d./d is the label to automatically backport to the 7./d branch. /d is the digit

NOTE: backport-skip has been added to this pull request.

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[andrew-goldstein]

Consider Claude 3.5 Sonnet

[nastasha-solomon]

Left one question that needs your input. Everything else looks good though!

[andrew-goldstein]

Thanks @benironside for these updates!
LGTM 🚀