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
Generalize the native fullscreen pass and descriptor plumbing so managed SRP can request shader-driven fullscreen stages without being locked to the ColorScale path.
Keep ColorScale as a convenience descriptor mapped to the builtin color-scale shader, and add native fullscreen factory coverage for the new shader-vector path.
