Add Windows runner files for high DPI support and console output

- Created runner.exe.manifest to enable DPI awareness and dark mode support.
- Implemented utility functions in utils.cpp and utils.h for console creation and command line argument handling.
- Developed Win32Window class in win32_window.cpp and win32_window.h to manage high DPI-aware windows, including theme updates and message handling.

lib/platform/window_state_stub.dart

@@ -0,0 +1,13 @@
+import 'dart:ui';
+
+class WindowStateStore {
+  WindowStateStore._();
+
+  static final WindowStateStore instance = WindowStateStore._();
+
+  Future<Size?> loadWindowSize() async {
+    return null;
+  }
+
+  Future<void> saveWindowSize(Size size) async {}
+}