Add comprehensive error handling and debug output to diagnose blank screen

app.py

@@ -60,7 +60,10 @@ def rewrite_message(
 # ──────────────────────────────────────────────────────────────
 # Page setup & CSS
 # ──────────────────────────────────────────────────────────────
-st.set_page_config(page_title="MemMachine Chatbot", layout="wide")
+try:
+    st.set_page_config(page_title="MemMachine Chatbot", layout="wide")
+except Exception as e:
+    st.error(f"Failed to set page config: {e}")
 
 # Show import errors if any
 if not IMPORTS_SUCCESSFUL:
@@ -70,6 +73,9 @@ if not IMPORTS_SUCCESSFUL:
         st.code(IMPORT_TRACEBACK)
     st.stop()
 
+# Debug: Show that app is loading
+st.write("🚀 App is loading...")
+
 try:
     with open("./styles.css") as f:
         st.markdown(f"<style>{f.read()}</style>", unsafe_allow_html=True)
@@ -80,20 +86,40 @@ except FileNotFoundError:
 # ──────────────────────────────────────────────────────────────
 # Sidebar
 # ──────────────────────────────────────────────────────────────
-with st.sidebar:
-    try:
-        st.image("./assets/memmachine_logo.png", use_container_width=True)
-    except FileNotFoundError:
-        st.markdown("### MemMachine")
-
-    st.markdown("#### Choose Model")
+try:
+    with st.sidebar:
+        try:
+            st.image("./assets/memmachine_logo.png", use_container_width=True)
+        except (FileNotFoundError, Exception) as e:
+            st.markdown("### MemMachine")
 
-    model_id = st.selectbox(
-        "Choose Model", MODEL_CHOICES, index=0, label_visibility="collapsed"
-    )
-    provider = MODEL_TO_PROVIDER[model_id]
-    set_model(model_id)
+        st.markdown("#### Choose Model")
 
+        try:
+            model_id = st.selectbox(
+                "Choose Model", MODEL_CHOICES, index=0, label_visibility="collapsed"
+            )
+            provider = MODEL_TO_PROVIDER[model_id]
+            set_model(model_id)
+        except Exception as e:
+            st.error(f"Error in model selection: {e}")
+            model_id = MODEL_CHOICES[0] if MODEL_CHOICES else "gpt-4.1-mini"
+            provider = MODEL_TO_PROVIDER.get(model_id, "openai")
+            set_model(model_id)
+except Exception as e:
+    st.error(f"Error initializing sidebar: {e}")
+    import traceback
+    st.code(traceback.format_exc())
+    # Set defaults
+    model_id = MODEL_CHOICES[0] if MODEL_CHOICES else "gpt-4.1-mini"
+    provider = MODEL_TO_PROVIDER.get(model_id, "openai")
+    selected_persona = "Charlie"
+    persona_name = "Charlie"
+    skip_rewrite = False
+    compare_personas = False
+    show_rationale = False
+else:
+    # Continue with sidebar if no exception
     st.markdown("#### Choose user persona")
     selected_persona = st.selectbox(
         "Choose user persona",
@@ -159,7 +185,12 @@ def append_user_turn(msgs: list[dict], new_user_msg: str) -> list[dict]:
 # ──────────────────────────────────────────────────────────────
 # Title
 # ──────────────────────────────────────────────────────────────
-st.title("MemMachine Chatbot")
+try:
+    st.title("MemMachine Chatbot")
+except Exception as e:
+    st.error(f"Error rendering title: {e}")
+    import traceback
+    st.code(traceback.format_exc())
 
 # ──────────────────────────────────────────────────────────────
 # Chat logic