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/server/rag_request.py

@@ -0,0 +1,25 @@
+from pydantic import BaseModel, Field
+
+from src.rag.retriever import Resource
+
+
+class RAGConfigResponse(BaseModel):
+    """Response model for RAG config."""
+
+    provider: str | None = Field(
+        None, description="The provider of the RAG, default is ragflow"
+    )
+
+
+class RAGResourceRequest(BaseModel):
+    """Request model for RAG resource."""
+
+    query: str | None = Field(
+        None, description="The query of the resource need to be searched"
+    )
+
+
+class RAGResourcesResponse(BaseModel):
+    """Response model for RAG resources."""
+
+    resources: list[Resource] = Field(..., description="The resources of the RAG")