Add image of playground (#145)

README.md

@@ -218,6 +218,8 @@ adds of these endpoints to the server:
 
 You can find a playground page for your runnable at `/my_runnable/playground`. This exposes a simple UI to [configure](https://python.langchain.com/docs/expression_language/how_to/configure) and invoke your runnable with streaming output and intermediate steps.
 
+![image](https://github.com/langchain-ai/langserve/assets/3205522/5ca56e29-f1bb-40f4-84b5-15916384a276)
+
 ## Installation
 
 For both client and server:
@@ -389,4 +391,4 @@ class FileProcessingRequest(CustomUserType):
     file: str = Field(..., extra={"widget": {"type": "base64file"}})
     num_chars: int = 100
 
-```
+```