Add error handling for imports to diagnose blank screen issue

app.py

@@ -1,16 +1,37 @@
 import os
+import sys
+import traceback
 from typing import cast
 
 import streamlit as st
-from gateway_client import delete_profile, ingest_and_rewrite
-from llm import chat, set_model
-from model_config import MODEL_CHOICES, MODEL_TO_PROVIDER
 
 # Configure Streamlit for Hugging Face Spaces
 # Port is set via command line argument in Dockerfile
 # Don't set STREAMLIT_SERVER_PORT here to avoid conflicts
 os.environ["STREAMLIT_SERVER_ADDRESS"] = "0.0.0.0"
 
+# Try to import modules with error handling
+try:
+    from gateway_client import delete_profile, ingest_and_rewrite
+    from llm import chat, set_model
+    from model_config import MODEL_CHOICES, MODEL_TO_PROVIDER
+    IMPORTS_SUCCESSFUL = True
+except Exception as e:
+    IMPORTS_SUCCESSFUL = False
+    IMPORT_ERROR = str(e)
+    IMPORT_TRACEBACK = traceback.format_exc()
+    # Create dummy functions to prevent NameError
+    def delete_profile(user_id: str) -> bool:
+        return False
+    def ingest_and_rewrite(user_id: str, query: str, model_type: str = "openai") -> str:
+        return query
+    def chat(messages, persona):
+        return "Error: Could not initialize chat function", 0, 0, 0
+    def set_model(model_id: str) -> None:
+        pass
+    MODEL_CHOICES = ["gpt-4.1-mini"]
+    MODEL_TO_PROVIDER = {"gpt-4.1-mini": "openai"}
+
 
 def rewrite_message(
     msg: str, persona_name: str, show_rationale: bool, skip_rewrite: bool, provider: str = "openai"
@@ -40,6 +61,15 @@ def rewrite_message(
 # Page setup & CSS
 # ──────────────────────────────────────────────────────────────
 st.set_page_config(page_title="MemMachine Chatbot", layout="wide")
+
+# Show import errors if any
+if not IMPORTS_SUCCESSFUL:
+    st.error("⚠️ Application Error: Failed to import required modules")
+    st.error(f"Error: {IMPORT_ERROR}")
+    with st.expander("Show full error details"):
+        st.code(IMPORT_TRACEBACK)
+    st.stop()
+
 try:
     with open("./styles.css") as f:
         st.markdown(f"<style>{f.read()}</style>", unsafe_allow_html=True)