feat(comparison): Add upstream vs sideline comparison framework

- Add comparison_presets.toml with 20+ preset configurations
- Add comparison_capture.py for frame capture and comparison
- Add run_comparison.py for running comparisons
- Add test_comparison_framework.py with comprehensive tests
- Add capture_upstream_comparison.py for upstream frame capture
- Add tomli to dev dependencies for TOML parsing

The framework supports:
- Multiple preset configurations (basic, effects, camera, source, viewport)
- Frame-by-frame comparison with detailed diff analysis
- Performance metrics comparison
- HTML report generation
- Integration with sideline branch for regression testing

pyproject.toml

@@ -65,6 +65,7 @@ dev = [
     "pytest-cov>=4.1.0",
     "pytest-mock>=3.12.0",
     "ruff>=0.1.0",
+    "tomli>=2.0.0",
 ]
 
 [tool.pytest.ini_options]