Lower Python requirement to >=3.9 and verify install in conda+docker …

[tawsifazad23]

…(#66)

• Lowered minimum Python requirement in pyproject.toml from 3.10 → 3.9
• Verified editable install and import under:
  • Conda environment (Python 3.9) - pip install -e . succeeded; import chatdbg works
  • Docker python:3.9 image (GDB uses Python 3.13) - added /work/src to sys.path for import
• Confirmed why executes without old_stuff.chatdbg_utils AttributeError