Promote stroke commit request assembly task

docs/modernization/tasks.md

@@ -1220,6 +1220,33 @@ Completed Task Log:
 | --- | --- | ---: | --- | --- |
 | 2026-06-13 | STR-013 | +1 renderer boundary and OpenGL parity | `ctest --preset desktop-fast --build-config Debug -R "pp_paint_renderer_stroke_execution|pp_paint_renderer_compositor" --output-on-failure` | `6220f333` |
 
+### STR-014 - Extract Stroke Commit Request Assembly
+
+Status: Ready
+Score: +1 renderer boundary and OpenGL parity
+Debt: `DEBT-0036`
+Scope: `src/canvas.cpp`, `tests/paint_renderer/compositor_tests.cpp`
+
+Goal:
+
+Move the face array assembly and commit request construction out of
+`Canvas::stroke_commit()` so the callsite only triggers the retained commit
+sequence with concrete state.
+
+Done Checks:
+
+- `Canvas::stroke_commit()` no longer builds the face array inline.
+- Regression coverage proves the request assembly helper preserves dirty-face
+  ordering.
+- `docs/modernization/debt.md` records the reduced stroke-commit request
+  assembly surface.
+
+Validation:
+
+```powershell
+ctest --preset desktop-fast --build-config Debug -R "pp_paint_renderer_stroke_execution|pp_paint_renderer_compositor" --output-on-failure
+```
+
 ### STR-011 - Extract Preview Main Pass Orchestration
 
 Status: Done