Route default clear through renderer GL

docs/modernization/roadmap.md

@@ -521,6 +521,9 @@ operation order.
 OpenGL runtime version/vendor/renderer/GLSL string queries now also use a
 tested `pp_renderer_gl` dispatch contract, leaving `App::init` to log the
 result while the backend owns the query set and order.
+The default app clear color and color-buffer clear operation now dispatch
+through `pp_renderer_gl` as well, moving another direct OpenGL operation out
+of `App::clear` while preserving the current gray clear behavior.
 Windows RenderDoc frame capture hooks now also dispatch through
 `PlatformServices`, keeping capture integration in the platform service while
 leaving non-Windows adapters as no-ops.