Share retained stroke sampler dispatch helpers

docs/modernization/roadmap.md

@@ -3119,6 +3119,10 @@ Results:
   destination bind/unbind, framebuffer copy callback wrapping, sample-point
   assembly, and brush-vertex upload/draw, while mixer-pass state execution and
   higher-level pass orchestration remain in the preview node.
+- `Canvas::stroke_draw` live-pass sampler bind/unbind plus semantic
+  texture-input dispatch now shares retained stroke execution helpers, while
+  concrete GL object mapping, framebuffer ownership, shader timing, and final
+  draw execution remain in the legacy Canvas path.
 - `Canvas::stroke_draw` pad-pass destination bind/copy/unbind ordering now
   shares the retained stroke execution helper callback surface, while shader
   setup, pad color selection, framebuffer ownership, and final OpenGL draw