Trim stroke mix shell

docs/modernization/debt.md

@@ -18,6 +18,10 @@ agent or engineer to remove them without reconstructing context from chat.
 
 ## Recent Reductions
 
+- 2026-06-13: `LATER-003` was narrowed again. `Canvas::stroke_draw_mix()` now
+  routes the full retained mix-pass shell through
+  `execute_legacy_canvas_stroke_mix_pass_with_setup(...)`; the live path
+  still owns the concrete framebuffer bind and GL capability toggles.
 - 2026-06-13: `LATER-003` was narrowed again. `Canvas::stroke_draw_mix()` now
   routes the setup/end shell through
   `make_legacy_canvas_stroke_mix_pass_setup(...)`; the live path still owns

docs/modernization/tasks.md

@@ -598,6 +598,9 @@ Progress Notes:
 - 2026-06-13: `Canvas::stroke_draw_mix()` now routes the setup/end shell through
   `make_legacy_canvas_stroke_mix_pass_setup(...)`; the live path still owns the
   concrete framebuffer bind and GL capability toggles.
+- 2026-06-13: `Canvas::stroke_draw_mix()` now routes the full retained mix-pass
+  shell through `execute_legacy_canvas_stroke_mix_pass_with_setup(...)`; the
+  live path still owns the concrete framebuffer bind and GL capability toggles.
 - 2026-06-13: `Canvas::stroke_draw()` live-pass sampler wiring now reuses a
   retained helper builder, and the stroke execution tests cover it. `STR-004`
   is now done after the final pad-destination helper extraction and tracker