Record STR-046 closeout hash

docs/modernization/debt.md

@@ -18,6 +18,10 @@ agent or engineer to remove them without reconstructing context from chat.
 
 ## Recent Reductions
 
+- 2026-06-14: `DEBT-0036` was narrowed again. `Canvas::draw_merge()` now
+  routes its plane iteration and branch orchestration through
+  `execute_canvas_draw_merge_plane_iteration(...)`; the canvas path still owns
+  the per-plane framebuffer setup and retained branch execution callbacks.
 - 2026-06-14: `DEBT-0036` was narrowed again. `execute_stroke_preview_final_composite_pass()`
   now routes the retained final-composite request construction through
   `make_stroke_preview_final_composite_request(...)`; the preview path still

docs/modernization/tasks.md

@@ -2023,7 +2023,7 @@ cmake --build --preset windows-msvc-default --config Debug --target PanoPainter
 
 ### STR-046 - Extract Draw Merge Plane Iteration Orchestration
 
-Status: Ready
+Status: Done
 Score: no score movement
 Debt: `DEBT-0036`
 Scope: `src/canvas.cpp`, `src/legacy_canvas_draw_merge_services.h`, `tests/paint_renderer/compositor_tests.cpp`
@@ -2043,6 +2043,8 @@ Done Checks:
 - `docs/modernization/debt.md` records the reduced draw-merge plane-loop
   surface.
 
+Closeout: `d46399f4`
+
 Validation:
 
 ```powershell