fix: discover wan_va package for installation

[Travor278]

Description

Updates the setuptools package discovery configuration so editable and regular installs discover the actual wan_va package tree.

This keeps the published project name (LingBot_VA) unchanged while fixing the Python package path used during build metadata generation. Existing source-tree imports such as python -m wan_va... continue to use the same module path.

Related Issue

No dedicated issue found. This was reproducible from the current main branch during install smoke testing.

Motivation and Context

pyproject.toml currently lists packages = ["lingbot_va"], but the repository contains wan_va/. As a result, pip install -e . --no-deps --dry-run fails before dependency installation with:

error: package directory 'lingbot_va' does not exist

Using setuptools package discovery for wan_va* makes the install metadata match the repository layout and includes subpackages under wan_va.

How Has This Been / Can This Be Tested?

Environment: WSL2 Ubuntu2204, Python 3.10.12 venv at /home/Travor/venvs/starvla-332.

python -m pip install -e . --no-deps --dry-run

Result:

Would install LingBot_VA-0.0.0

Also ran:

git diff --check origin/main...HEAD

Checklist

• Keeps the public project name unchanged.
• Discovers wan_va and nested wan_va.* packages.
• Does not change runtime dependencies or model code.