Add Mistral to free models

app.py

@@ -25,6 +25,7 @@ FREE_MODEL_CHOICES = [
     "meta-llama/Llama-4.1-8B-Instruct:novita",
     "gemini-2.5-flash",
     "gpt-4o",
+    "mistral-large-latest",
 ]
 
 # Paid models (user provides their own API key)
@@ -117,6 +118,10 @@ def classify_data(spreadsheet_file, spreadsheet_column,
             actual_api_key = os.environ.get("GOOGLE_API_KEY", "")
             if not actual_api_key:
                 return None, None, "**Error:** Google API key not configured in Space secrets"
+        elif "mistral" in model.lower():
+            actual_api_key = os.environ.get("MISTRAL_API_KEY", "")
+            if not actual_api_key:
+                return None, None, "**Error:** Mistral API key not configured in Space secrets"
         else:
             actual_api_key = os.environ.get("HF_API_KEY", "")
     else: