Refactor docstring in handle_message function for clarity

Updated the docstring to provide a clearer description of the function's purpose and parameters in app.py.

app.py

@@ -1,20 +1,20 @@
 import gradio as gr
+
+from config import DEFAULT_PERSONA
 from prompts import PERSONAS
 from utils import generate_response
-from config import DEFAULT_PERSONA
 
 
 def handle_message(persona, user_input, history):
-    """
-    Handle a new message in the chat.
-
+    """Process a chat message and return updated history.
+    
     Args:
-        persona (str): The selected persona
-        user_input (str): The user's message
-        history (list): Chat history in messages format
-
-    Returns:l
-        list: Updated chat history with new messages
+        persona: Selected chat persona
+        user_input: User's message
+        history: Previous chat messages
+        
+    Returns:
+        Updated chat history with new messages
     """
     # Validate inputs
     if not persona or persona not in PERSONAS: