WIP, but working basic search using initial tool choice node

backend/onyx/chat/prompt_builder/answer_prompt_builder.py

@@ -4,6 +4,7 @@ from typing import cast
 from langchain_core.messages import BaseMessage
 from langchain_core.messages import HumanMessage
 from langchain_core.messages import SystemMessage
+from pydantic import BaseModel
 from pydantic.v1 import BaseModel as BaseModel__v1
 
 from onyx.chat.models import PromptConfig
@@ -182,6 +183,13 @@ class AnswerPromptBuilder:
         )
 
 
+# Stores some parts of a prompt builder as needed for tool calls
+class PromptSnapshot(BaseModel):
+    raw_message_history: list[PreviousMessage]
+    raw_user_query: str
+    built_prompt: list[BaseMessage]
+
+
 # TODO: rename this? AnswerConfig maybe?
 class LLMCall(BaseModel__v1):
     prompt_builder: AnswerPromptBuilder