Fix JSON parsing in OpenAI response handling

app.py

@@ -71,8 +71,11 @@ def classify_with_openai(image_path):
     )
 
     try:
-        parsed_response = json.loads(response.output_text)
-    except json.JSONDecodeError:
+        text = response.output_text.strip()
+        if text.startswith("```"):
+            text = text.split("\n", 1)[1].rsplit("```", 1)[0].strip()
+        parsed_response = json.loads(text)
+    except (json.JSONDecodeError, IndexError):
         parsed_response = {
             "raw_response": response.output_text,
             "warning": "OpenAI response was not valid JSON.",