Refactor imports and enhance query functionality with LangGraph integration; update requirements for new dependencies

app/main.py

@@ -1,11 +1,12 @@
 import io
 
 import pandas as pd
-from db.db import db_dependency, init_database
+from app.db.db import db_dependency, init_database
 from fastapi import FastAPI, File, UploadFile
-from services.openrouter import InvestorProcessor
+from app.services.openrouter import InvestorProcessor
 
-from app.services.querying import QueryProcessor
+from app.pydantic_schemas import QueryRequest, QueryResponseList
+from app.services.langgraph_agent import LangGraphQueryAgent
 
 app = FastAPI()
 
@@ -31,11 +32,11 @@ async def parse_csv(db: db_dependency, file: UploadFile = File(...)):
     return {"results": [r.dict() for r in results]}
 
 
-@app.post("/query")
-async def query_investors(db: db_dependency, question: str):
-    processor = QueryProcessor(sql_session=db)
-    results = processor.process_query(question)
-    return {"results": [r.dict() for r in results]}
+@app.post("/query", response_model=QueryResponseList)
+async def query_investors(db: db_dependency, request: QueryRequest):
+    agent = LangGraphQueryAgent(sql_session=db)
+    result = agent.run(request.question)
+    return result
 
 
 if __name__ == "__main__":