Feature/sse (#3125)

* Base changes for ServerSide Events (instead of socket.io)

* lint fixes

* adding of interface and separate methods for streaming events

* lint

* first draft, handles both internal and external prediction end points.

* lint fixes

* additional internal end point for streaming and associated changes

* return streamresponse as true to build agent flow

* 1) JSON formatting for internal events
2) other fixes

* 1) convert internal event to metadata to maintain consistency with external response

* fix action and metadata streaming

* fix for error when agent flow is aborted

* prevent subflows from streaming and other code cleanup

* prevent streaming from enclosed tools

* add fix for preventing chaintool streaming

* update lock file

* add open when hidden to sse

* Streaming errors

* Streaming errors

* add fix for showing error message

---------

Co-authored-by: Henry <hzj94@hotmail.com>

packages/components/src/Interface.ts

@@ -400,3 +400,22 @@ export interface IStateWithMessages extends ICommonObject {
     messages: BaseMessage[]
     [key: string]: any
 }
+
+export interface IServerSideEventStreamer {
+    streamEvent(chatId: string, data: string): void
+    streamStartEvent(chatId: string, data: any): void
+
+    streamTokenEvent(chatId: string, data: string): void
+    streamCustomEvent(chatId: string, eventType: string, data: any): void
+
+    streamSourceDocumentsEvent(chatId: string, data: any): void
+    streamUsedToolsEvent(chatId: string, data: any): void
+    streamFileAnnotationsEvent(chatId: string, data: any): void
+    streamToolEvent(chatId: string, data: any): void
+    streamAgentReasoningEvent(chatId: string, data: any): void
+    streamNextAgentEvent(chatId: string, data: any): void
+    streamActionEvent(chatId: string, data: any): void
+
+    streamAbortEvent(chatId: string): void
+    streamEndEvent(chatId: string): void
+}