[8.x] [8.16] AI usecase updates (backport #6076)

[mergify]

Fixes #6005 by updating the three AI Usecase guides in the AI for Security section. Lots of screenshot updates and some minor text updates

Previews:
ESQL usecase (ESS) (Serverless)
Alert triage usecase (ESS) (Serverless)
Incident reporting usecase (ESS) (Serverless)

---

This is an automatic backport of pull request #6076 done by Mergify.

[mergify]

Cherry-pick of 21b9b46 has failed:

On branch mergify/bp/8.x/pr-6076
Your branch is up to date with 'origin/8.x'.

You are currently cherry-picking commit 21b9b461.
  (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/ai-triage-add-to-case.png
	modified:   docs/AI-for-security/images/attck-disc-11-alerts-disc.png
	modified:   docs/AI-for-security/images/attck-disc-esql-query-gen-example.png
	deleted:    docs/AI-for-security/images/attck-disc-remediate-sodinokibi.gif
	new file:   docs/AI-for-security/images/attck-disc-remediate-threat.gif
	modified:   docs/AI-for-security/images/attck-disc-translate-japanese.png
	modified:   docs/AI-for-security/usecase-alert-triage.asciidoc
	modified:   docs/AI-for-security/usecase-attack-discovery-ai-assistant-incident-reporting.asciidoc
	modified:   docs/AI-for-security/usecase-esql-queries.asciidoc
	new file:   docs/serverless/AI-for-security/images/attck-disc-remediate-threat.gif

Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)
	deleted by us:   docs/serverless/AI-for-security/ai-assistant-alert-triage.asciidoc
	deleted by us:   docs/serverless/AI-for-security/ai-assistant-esql-queries.asciidoc
	deleted by us:   docs/serverless/AI-for-security/images/attck-disc-11-alerts-disc.png
	deleted by us:   docs/serverless/AI-for-security/images/attck-disc-translate-japanese.png
	deleted by us:   docs/serverless/AI-for-security/usecase-attack-disc-ai-assistant-incident-reporting.asciidoc
	deleted by us:   docs/serverless/images/ai-assistant-alert-triage/ai-triage-add-to-case.png

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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