Add warning on sign in with hf

ui.py

@@ -116,7 +116,7 @@ def _render_header():
         with gr.Row():
             gr.LoginButton(value="Sign in with Hugging Face")
             with gr.Column(scale=3):
-                gr.Markdown("")
+                gr.Markdown("⚠️ **Warning:** Signing in will refresh the page and reset your current session (including data and model progress).")
 
 def _render_dataset_tab(engine_state):
     with gr.TabItem("1. Preparing Dataset"):