Bind Win32 main-thread queue to runtime state

docs/modernization/roadmap.md

@@ -70,6 +70,11 @@ What is already real:
 - `pp_app_core`
 
 Latest slice:
+- `src/platform_windows/windows_platform_services.cpp` no longer brokers the
+  Win32 main-thread queue through `bound_app()->runtime()`; it now uses an
+  explicit Windows runtime binding.
+- `src/platform_windows/windows_runtime_state.*` now carries the active
+  `AppRuntime*` binding beside the retained Windows-owned runtime objects.
 - `src/platform_windows/windows_runtime_state.*` now owns the retained Win32
   runtime object lifetime (`App`, `WacomTablet`) instead of leaving that
   storage inside `windows_runtime_shell.cpp`.

docs/modernization/tasks.md

@@ -78,6 +78,10 @@ Completed, blocked, and superseded task history moved to
   the queue is now ordered by code movement instead.
 
 Current slice:
+- `src/platform_windows/windows_platform_services.cpp` no longer uses
+  `bound_app()->runtime()` for main-thread task brokering.
+- `src/platform_windows/windows_runtime_state.*` now carries the active
+  `AppRuntime*` binding used by that queue hook.
 - `src/platform_windows/windows_runtime_state.*` now owns the retained Win32
   runtime object lifetime (`App`, `WacomTablet`).
 - `src/platform_windows/windows_runtime_shell.cpp` no longer carries that

src/platform_windows/windows_platform_services.cpp

@@ -5,6 +5,7 @@
 #include "platform_windows/windows_main_window_session.h"
 #include "platform_windows/windows_platform_services.h"
 #include "platform_windows/windows_runtime_shell.h"
+#include "platform_windows/windows_runtime_state.h"
 #include "keymap.h"
 #include "platform_windows/windows_stylus_input.h"
 #include "platform_windows/windows_window_shell.h"
@@ -142,9 +143,9 @@ namespace {
 
 void enqueue_main_thread_task(std::packaged_task<void()> task)
 {
-    if (auto* app = bound_app())
+    if (auto* runtime = retained_bound_runtime())
     {
-        app->runtime().main_thread_task(std::move(task));
+        runtime->main_thread_task(std::move(task));
         return;
     }
 
@@ -156,9 +157,9 @@ void enqueue_main_thread_task(std::packaged_task<void()> task)
 
 void drain_main_thread_tasks()
 {
-    if (auto* app = bound_app())
+    if (auto* runtime = retained_bound_runtime())
     {
-        app->runtime().drain_main_thread_tasks();
+        runtime->drain_main_thread_tasks();
         return;
     }
 }

src/platform_windows/windows_runtime_shell.cpp

@@ -120,6 +120,7 @@ App* bound_app() noexcept
 void release_bound_app() noexcept
 {
     bind_app(nullptr);
+    bind_runtime(nullptr);
     retained_owned_app().reset();
 }
 
@@ -136,6 +137,7 @@ int run_main_application(int argc, char** argv)
     owned_app = std::make_unique<App>();
     auto* app = owned_app.get();
     bind_app(app);
+    bind_runtime(&app->runtime());
     app->set_platform_services(&pp::platform::windows::platform_services());
     app->initLog();
 

src/platform_windows/windows_runtime_state.cpp

@@ -3,6 +3,7 @@
 #include "platform_windows/windows_runtime_state.h"
 
 #include "app.h"
+#include "app_runtime.h"
 #include "wacom.h"
 
 namespace pp::platform::windows {
@@ -10,6 +11,7 @@ namespace {
 
 struct RetainedWindowsRuntimeState final {
     std::unique_ptr<App> owned_app;
+    AppRuntime* runtime = nullptr;
     WacomTablet tablet;
 };
 
@@ -31,4 +33,14 @@ WacomTablet& retained_wacom_tablet() noexcept
     return retained_runtime_state().tablet;
 }
 
+AppRuntime* retained_bound_runtime() noexcept
+{
+    return retained_runtime_state().runtime;
+}
+
+void bind_runtime(AppRuntime* runtime) noexcept
+{
+    retained_runtime_state().runtime = runtime;
+}
+
 }

src/platform_windows/windows_runtime_state.h

@@ -3,11 +3,14 @@
 #include <memory>
 
 class App;
+class AppRuntime;
 class WacomTablet;
 
 namespace pp::platform::windows {
 
 [[nodiscard]] std::unique_ptr<App>& retained_owned_app() noexcept;
 [[nodiscard]] WacomTablet& retained_wacom_tablet() noexcept;
+[[nodiscard]] AppRuntime* retained_bound_runtime() noexcept;
+void bind_runtime(AppRuntime* runtime) noexcept;
 
 }