[Security Solution] [AI assistant] Include in documentation changes to ES|QL generation in the security AI assistant (#2168)

Closes: elastic/docs-content-internal#102

Update Security documentation to reflect changes to how the Security AI
assistant generates ES|Ql.

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Co-authored-by: florent-leborgne <[email protected]>

Author: KDKHD

solutions/security/ai/ai-assistant.md

@@ -165,6 +165,10 @@ The **Knowledge base** tab of the **Security AI settings** page allows you to en
 
 Elastic AI Assistant allows you to take full advantage of the {{elastic-sec}} platform to improve your security operations. It can help you write an {{esql}} query for a particular use case, or answer general questions about how to use the platform. Its ability to assist you depends on the specificity and detail of your questions. The more context and detail you provide, the more tailored and useful its responses will be.
 
+:::{note}
+{applies_to}`stack: ga 9.1` {applies_to}`serverless: ga` The agent has access to index names and field metadata from your cluster. This contextual information helps improve ES|QL generation, though it may slightly increase response times.
+:::
+
 To maximize its usefulness, consider using more detailed prompts or asking for additional information. For instance, after asking for an {{esql}} query example, you could ask a follow-up question like, “Could you give me some other examples?” You can also ask for clarification or further exposition, for example "Provide comments explaining the query you just gave."
 
 In addition to practical advice, AI Assistant can offer conceptual advice, tips, and best practices for enhancing your security measures. You can ask it, for example: