change assistant to model

app.py

@@ -165,9 +165,22 @@ async def stream_response_gemini(query, history):
     # 2) Build only user/model history as `contents`
     contents = []
     for msg in history:
+        # Ensure the role is compatible with Gemini API ('user' or 'model')
+        api_role = ""
+        if msg["role"] == "user":
+            api_role = "user"
+        elif msg["role"] == "assistant":  # Map "assistant" from client to "model" for API
+            api_role = "model"
+        elif msg["role"] == "model": # Already correct
+            api_role = "model"
+        else:
+            # Log a warning or handle unrecognized roles as needed
+            logger.warning(f"Unrecognized role '{msg['role']}' in history. Skipping message.")
+            continue
+
         contents.append(
             types.Content(
-                role=msg["role"], 
+                role=api_role, 
                 parts=[ types.Part.from_text(text=msg["content"]) ]
             )
         )