Implemented logout

app.py

@@ -85,7 +85,11 @@ def init_interface(
             - scenario_text: The scenario text for the user to act out.
             - progress_bar: Visual progress bar showing completed scenarios.
     """
-    welcome_msg = f"""## 👋 Welcome {username}! Please follow these steps to contribute to our dataset:
+    welcome_msg = f"""## 👋 Welcome {username}!
+
+[Logout](/logout)
+
+### Please follow these steps to contribute to our dataset:
 
 1. **Understand the Scenario**: Carefully read the scenario provided. This describes the situation you need to act out.