fix: Fixed runtime crash due to uninitialized variable

app.py

@@ -18,6 +18,7 @@ def format_prompt(message, history):
     logging.debug("Input Message: %s", message)
     logging.debug("Input History: %s", history)
 
+    prompt = ""
     for user_prompt, bot_response in history:
         prompt += f"<s> [INST] {user_prompt} [/INST]"
         prompt += f" {bot_response}</s> "