Adds integration tests exercising the full ReorientFaceMesh -> RenderTexturedFaceMesh data flow with synthetic inputs, verifying output shape contracts and value ranges. Also adds pytest.ini and conftest.py for standalone test execution, guards __init__.py relative imports with try/except for pytest 8.x Package compatibility, and removes tests/ from .gitignore. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>