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,

docs/modernization/roadmap.md

@@ -104,7 +104,9 @@ Current architecture mismatches that must be treated as real blockers:
   while Linux/Web GLFW render-context acquire/present and Linux app-close now
   route through retained local GLFW callback hooks, and retained Apple ObjC
   handles plus storage paths now sit behind one local `platform_legacy`
-  helper instead of being re-read through `App::I` in each touched path.
+  helper instead of being re-read through `App::I` in each touched path, with
+  the retained GLFW window hooks and fallback storage-path return now also
+  using local retained-state helpers instead of direct method-body reads.
 - `src/platform_legacy/legacy_platform_services.*` is still part of the live
   app shell.
 - `pp_panopainter_ui` still depends on `pp_legacy_app`.
@@ -115,7 +117,8 @@ Current architecture mismatches that must be treated as real blockers:
   checkerboard background setup now route through retained draw-merge helpers,
   with the cache-to-screen checkerboard-plane callback setup also reduced and
   the merged-path per-plane merged-texture draw plus the smoothing-mask face
-  shader/draw pass now routed through the same retained helper family.
+  shader/draw pass plus heightmap callback setup now routed through the same
+  retained helper family.
 - `app_layout.cpp` and `app_dialogs.cpp` are still mixed shell/controller files
   rather than thin composition/binding surfaces.
 - `App`, `Canvas`, `Node`, retained workers, and platform entrypoints still use
@@ -128,7 +131,9 @@ Current architecture mismatches that must be treated as real blockers:
   also use owned `std::jthread` lifecycle, `LogRemote` now uses the same
   ownership model, the Windows VR device now has explicit `std::unique_ptr`
   ownership instead of raw global lifetime, and the Windows main-loop/VR
-  coordination flags now use `std::atomic` instead of unsynchronized globals.
+  coordination flags now use `std::atomic` instead of unsynchronized globals,
+  while the main Win32 entrypoint now groups window/GL/task/VR state behind a
+  retained local state object instead of separate process-wide globals.
 - Modern C++23 usage exists in extracted components, especially `std::span`,
   explicit result/status objects, and a few concepts, but the live app still
   does not consistently express ownership, thread affinity, or renderer

docs/modernization/tasks.md

@@ -143,6 +143,9 @@ Current slice:
   draw, heightmap draw, and current-mode draw now also route through
   `execute_legacy_canvas_draw_merge_post_draw(...)`, but broader canvas draw
   orchestration is still inline.
+- `NodeCanvas` heightmap draw callback setup now also routes through
+  `make_legacy_canvas_draw_merge_heightmap_draw(...)`, but the node still owns
+  current-mode traversal and broader post-draw orchestration.
 - `NodeCanvas` smoothing-mask face shader setup plus per-face draw execution
   now also route through
   `execute_legacy_canvas_draw_merge_smask_faces(...)`, but the node still owns
@@ -341,6 +344,9 @@ Current slice:
   explicit stop requests instead of raw `std::thread`
 - Windows main-loop run-state and VR worker coordination flags in `main.cpp`
   now use `std::atomic` ownership instead of unsynchronized globals
+- `main.cpp` Win32 window handles, GL task/mutex state, splash-dialog state,
+  stylus timers, and VR worker state now sit behind one retained local state
+  object instead of separate file-scope globals
 - retained `App` composition, task call sites, and platform/runtime entrypoint
   coupling are still not fully reduced behind the runtime contract
 
@@ -616,6 +622,9 @@ Current slice:
 - Linux/Web GLFW render-context acquire/present hooks and Linux app-close now
   also route through retained local GLFW callback hooks instead of direct
   method-body `App::I` access in `LegacyPlatformServices`
+- retained GLFW window hooks and the non-Linux fallback storage-path return now
+  also route through retained local state helpers instead of reading `App::I`
+  directly in those method bodies
 - retained Apple callback injection and broader `platform_legacy` singleton
   reach are still open