Key points:\n- restore the tests tree removed by bc47e6e\n- capture current editor workspace, scene, and docs reshuffle changes\n- keep local cloud.nvdb resources ignored from this commit
- Add triangle test with vertex buffer and custom pipeline state
- Add triangle.hlsl shader with position and color per vertex
- Fix cull mode (NONE) and disable depth test for correct rendering
- Register D3D12_Triangle_Integration CTest
- Add GT.ppm golden image
