test: add test for per-attack image directories and improve error handling

- Add test_generate_test_cases.py to verify each attack uses its own image directory
- Improve error messages in unified_registry for failed imports with more context
- Add null checks in generate_test_cases.py for attack initialization failures
- Reduce excessive max_tokens in judge_utils from 130000 to 10000 for efficiency
- Add missing ThreadPoolExecutor import in qr/attack.py
- Fix missing newline in pyproject.toml

attacks/qr/attack.py

@@ -14,6 +14,7 @@ from PIL import Image, ImageFont, ImageDraw
 import torch
 import threading
 import logging
+from concurrent.futures import ThreadPoolExecutor
 
 from core.data_formats import TestCase
 from core.base_classes import BaseAttack