Fix 404 error: Update model from deprecated claude-3-opus to claude-sonnet-4

The claude-3-opus-20240229 model is no longer available, causing 404 errors.
Updated all model references to claude-sonnet-4-20250514.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app.py

@@ -223,7 +223,7 @@ else:
                         })
 
                 response = client.messages.create(
-                    model="claude-3-opus-20240229",
+                    model="claude-sonnet-4-20250514",
                     messages=formatted_messages,
                     max_tokens=1024
                 )
@@ -327,7 +327,7 @@ Tone: Warm, precise, emotionally attuned. Do not overuse praise, avoid pathologi
                 try:
                     # Get the initial response using the system message as a parameter
                     response = client.messages.create(
-                        model="claude-3-opus-20240229",
+                        model="claude-sonnet-4-20250514",
                         system=debrief_system_message,
                         messages=[{"role": "user", "content": "Please help me process this conversation."}],
                         max_tokens=1000
@@ -361,7 +361,7 @@ Tone: Warm, precise, emotionally attuned. Do not overuse praise, avoid pathologi
                 with st.spinner("Reflecting..."):
                     try:
                         response = client.messages.create(
-                            model="claude-3-opus-20240229",
+                            model="claude-sonnet-4-20250514",
                             system=debrief_system_message,
                             messages=[
                                 {"role": "user", "content": msg["content"]} 

src/streamlit_app.py

@@ -57,7 +57,7 @@ try:
     # Test the client
     st.write("Debug: Testing API connection...")
     test_response = anthropic.messages.create(
-        model="claude-3-opus-20240229",
+        model="claude-sonnet-4-20250514",
         max_tokens=10,
         messages=[{"role": "user", "content": "test"}]
     )
@@ -147,7 +147,7 @@ if st.session_state.messages and not st.session_state.in_debrief and not st.sess
         
         # Get initial debrief response
         response = anthropic.messages.create(
-            model="claude-3-opus-20240229",
+            model="claude-sonnet-4-20250514",
             max_tokens=1000,
             messages=st.session_state.debrief_messages
         )
@@ -181,7 +181,7 @@ if st.session_state.in_debrief:
         with st.chat_message("assistant"):
             with st.spinner("Reflecting..."):
                 response = anthropic.messages.create(
-                    model="claude-3-opus-20240229",
+                    model="claude-sonnet-4-20250514",
                     max_tokens=1000,
                     messages=st.session_state.debrief_messages
                 )
@@ -226,7 +226,7 @@ elif st.session_state.messages and not st.session_state.practice_complete:
                     st.write(f"Debug: Using API key starting with: {api_key[:10]}...")
                     
                     response = anthropic.messages.create(
-                        model="claude-3-opus-20240229",
+                        model="claude-sonnet-4-20250514",
                         max_tokens=1000,
                         messages=st.session_state.messages
                     )