Retain Win32 entry state and trim canvas/platform seams

docs/modernization/debt.md

@@ -18,6 +18,23 @@ agent or engineer to remove them without reconstructing context from chat.
 
 ## Reductions
 
+- 2026-06-16: `DEBT-0003` was narrowed again. `src/main.cpp` now keeps Win32
+  window handles, GL/task mutex state, stylus timers, splash-dialog state, and
+  VR worker state behind one retained local state object instead of separate
+  file-scope globals; retained entrypoint orchestration, direct `App::I`
+  mutation, and broader platform/runtime coupling remain.
+- 2026-06-16: `DEBT-0017` was narrowed again. Retained GLFW window hooks and
+  the non-Linux fallback storage-path return in
+  `src/platform_legacy/legacy_platform_services.cpp` now route through local
+  retained-state helpers instead of direct method-body `App::I` reads; the
+  retained platform fallback adapter and broader platform-to-app singleton
+  reach remain.
+- 2026-06-16: `DEBT-0036` was narrowed again. `NodeCanvas` heightmap draw
+  callback setup now routes through
+  `make_legacy_canvas_draw_merge_heightmap_draw(...)` in
+  `src/legacy_canvas_draw_merge_services.h` instead of keeping that callback
+  body inline in `NodeCanvas::draw()`; broader canvas draw orchestration and
+  retained GL resource ownership remain.
 - 2026-06-16: `DEBT-0003` was narrowed again. The Windows main-loop run-state
   and VR worker coordination flags in `src/main.cpp` now use `std::atomic`
   instead of unsynchronized globals; retained Win32 entrypoint ownership,