Update app.py

Add a guaranteed early render at top-level

app.py

@@ -5,6 +5,7 @@ import os
 # 0. GLOBAL CONFIG (Super Lightweight)
 # ==========================================
 st.set_page_config(page_title="AI Pneumonia Assistant", page_icon="🫁", layout="wide")
+st.write("✅ App booted successfully.")
 
 # define paths only (no file checks yet)
 BASE_DIR = "kaggle_checkpoints"