Extract dialog workflow, bootstrap, and canvas tail helpers

docs/modernization/tasks.md

@@ -205,6 +205,11 @@ Current slice:
   `make_node_canvas_layer_path_execution(...)` helper, which materially thins
   `NodeCanvas::draw()` even though the broader draw loop still lives in
   `src/node_canvas.cpp`.
+- `NodeCanvas` post-draw callback assembly, smoothing-mask face execution, and
+  optional display resolve now also route through
+  `execute_node_canvas_draw_merge_tail(...)`, which trims another live tail
+  block from `NodeCanvas::draw()` even though the broader outer draw shell is
+  still inline.
 
 Write scope:
 - `src/node_stroke_preview.cpp`
@@ -343,6 +348,9 @@ Current slice:
   `src/app_dialogs_export.cpp`, and the corresponding `App::dialog_*`
   entrypoints are now thin call-throughs, but new/open/save/browse/resize and
   retained dialog execution are still inline in `src/app_dialogs.cpp`.
+- New/open/save/browse/resize workflow entrypoints now also live in
+  `src/app_dialogs_workflow.cpp`, and `src/app_dialogs.cpp` is down to the
+  remaining thin entrypoints plus layer-rename retained dialog glue.
 
 Write scope:
 - `src/app_dialogs.cpp`
@@ -448,6 +456,10 @@ Current slice:
   state, now routes through `src/platform_windows/windows_vr_shell.h` instead
   of staying inline in `src/main.cpp`, but broader retained Win32 shell state
   is still open
+- RenderDoc startup/frame capture, SHCore DPI bootstrap, Win32 error-string
+  conversion, `UnadjustWindowRectEx`, and GL debug pre/post callbacks now also
+  live in `src/platform_windows/windows_bootstrap_helpers.cpp` instead of
+  `src/main.cpp`
 - prepared-file background work now runs through an `AppRuntime`-owned worker
   queue instead of a retained static worker in `src/app_events.cpp`
 - canvas async import/export/save/open background work now also runs through an