Add Streamlit demo

app.py

@@ -1,6 +1,12 @@
-# app.py
 import streamlit as st
 
-st.title("Spatial Parse Demo")
-x = st.slider('Select a value')
-st.write(x, 'squared is', x * x)
+st.title("Spatial Parser Demo")
+
+password = st.text_input("Enter access password:", type="password")
+
+if password != "demo1234":
+    st.warning("Please enter the correct password to continue.")
+    st.stop()
+
+# 👇真实内容放在这下面
+st.write("Welcome to the demo!")