feat: RAG Integration (#238)

* feat: add rag provider and retriever

* feat: retriever tool

* feat: add retriever tool to the researcher node

* feat: add rag http apis

* feat: new message input supports resource mentions

* feat: new message input component support resource mentions

* refactor: need_web_search to need_search

* chore: RAG integration docs

* chore: change example api host

* fix: user message color in dark mode

* fix: mentions style

* feat: add local_search_tool to researcher prompt

* chore: research prompt

* fix: ragflow page size and reporter with

* docs: ragflow integration and add acknowledgment projects

* chore: format

src/graph/types.py

@@ -1,12 +1,10 @@
 # Copyright (c) 2025 Bytedance Ltd. and/or its affiliates
 # SPDX-License-Identifier: MIT
 
-import operator
-from typing import Annotated
-
 from langgraph.graph import MessagesState
 
 from src.prompts.planner_model import Plan
+from src.rag import Resource
 
 
 class State(MessagesState):
@@ -15,6 +13,7 @@ class State(MessagesState):
     # Runtime Variables
     locale: str = "en-US"
     observations: list[str] = []
+    resources: list[Resource] = []
     plan_iterations: int = 0
     current_plan: Plan | str = None
     final_report: str = ""