[8.x] AD updates for 8.16 (backport #6114)

[mergify]

Fixes #6003 with a fresh PR to manage merge conflicts. Content was already reviewed/approved in #6013.

Preview: Attack discovery (ESS) (Serverless).

---

This is an automatic backport of pull request #6114 done by Mergify.

[mergify]

Cherry-pick of 88103ce has failed:

On branch mergify/bp/8.x/pr-6114
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit 88103ce2.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   docs/AI-for-security/images/add-discovery-to-assistant.gif
	modified:   docs/AI-for-security/images/attck-disc-11-alerts-disc.png
	new file:   docs/AI-for-security/images/attck-disc-alerts-number-menu.png
	new file:   docs/AI-for-security/images/attck-disc-example-disc.png
	new file:   docs/AI-for-security/images/attck-disc-rbac.png
	new file:   docs/AI-for-security/images/attck-disc-select-model-empty.png
	modified:   docs/AI-for-security/usecase-alert-triage.asciidoc
	new file:   docs/serverless/AI-for-security/images/add-discovery-to-assistant.gif
	new file:   docs/serverless/AI-for-security/images/attck-disc-example-disc.png
	new file:   docs/serverless/AI-for-security/images/attck-disc-rbac.png
	new file:   docs/serverless/AI-for-security/images/attck-disc-select-model-empty.png

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	both modified:   docs/AI-for-security/attack-discovery.asciidoc
	deleted by us:   docs/serverless/AI-for-security/ai-assistant-alert-triage.asciidoc
	deleted by us:   docs/serverless/AI-for-security/ai-for-security-landing-pg.asciidoc
	deleted by us:   docs/serverless/AI-for-security/attack-discovery.asciidoc
	deleted by us:   docs/serverless/AI-for-security/connect-to-byo-llm.asciidoc
	deleted by us:   docs/serverless/AI-for-security/images/attck-disc-11-alerts-disc.png
	deleted by us:   docs/serverless/AI-for-security/llm-connector-guides.asciidoc
	deleted by us:   docs/serverless/AI-for-security/llm-performance-matrix.asciidoc
	deleted by us:   docs/serverless/AI-for-security/usecase-attack-disc-ai-assistant-incident-reporting.asciidoc

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[github-actions]

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