[Security solution] AI Assistant, replace LLM with SimpleChatModel

[stephmilovic]

Summary

1. Replaces the LLM model and chat-conversational-react-description agent with the SimpleChatModel model and structured-chat-zero-shot-react-description agent for non-streaming AI Assistant requests.
2. Updates ESQLKnowledgeBaseTool from DynamicTool to DynamicStructuredTool

Here are some datasets using the updated ESQLKnowledgeBaseTool

SimpleChatModel - Sonnet
SimpleChatModel - Azure
ChatOpenAI - Azure

Still To Do

1. Update the AlertCountsTool and OpenAndAcknowledgedAlertsTool tools from DynamicTool to DynamicStructuredTool
2. Update the other usages of ActionsClientLlm with ActionsClientSimpleChatModel (post_evaluate and post_attack_discovery)
3. Experiment with updating the AttackDiscoveryTool to DynamicStructuredTool

May do the attack discovery stuff in a separate PR depending on what @andrew-goldstein thinks.

[stephmilovic]

handleParsingErrors can also be a function, so I put logs in here while developing. It was not hit once I added the agentArgs. However when I was hitting it, it did help to get the agent back on track so I think I should leave it. Here is an example of a run where it was hit: https://smith.langchain.com/public/910b7739-cd9a-401b-9db0-fe8438ff53e5/r