Extract canvas plane data, brush preset list, and WinMain bridge

src/platform_windows/windows_bootstrap_helpers.cpp

@@ -112,6 +112,24 @@ void ensure_runtime_data_directory()
     LOG("data files ok");
 }
 
+int run_winmain_entry(int (*entry_point)(int, char**))
+{
+    int argc = 0;
+
+    auto wargs = CommandLineToArgvW(GetCommandLine(), &argc);
+    auto argv = new char*[argc + 1];
+    for (int i = 0; i < argc; i++)
+    {
+        auto len = wcslen(wargs[i]) + 1;
+        argv[i] = new char[len];
+        wcstombs_s(nullptr, argv[i], len, wargs[i], len);
+    }
+
+    LocalFree(wargs);
+
+    return entry_point(argc, argv);
+}
+
 void setup_exception_handler()
 {
     // Setup exception handler