ModuleNotFoundError: No module named 'toolbox'

**Summary[问题简述（一句话）]**
Traceback (most recent call last):
File "D:\Haibara-Ai\modules\MockingBird-main\demo_toolbox.py", line 2, in
from toolbox import Toolbox
ModuleNotFoundError: No module named 'toolbox'

**Env & To Reproduce[复现与环境]**
python 3.9.10

Start with demo_toolbox.py and reproduce the import failure under Python 3.9.10. Inspect the project setup to determine why toolbox is unavailable; the issue is done when demo_toolbox.py can import Toolbox without raising ModuleNotFoundError.

Written by the indexing model from the issue text.