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.

macos/Runner/MainFlutterWindow.swift

@@ -0,0 +1,15 @@
+import Cocoa
+import FlutterMacOS
+
+class MainFlutterWindow: NSWindow {
+  override func awakeFromNib() {
+    let flutterViewController = FlutterViewController()
+    let windowFrame = self.frame
+    self.contentViewController = flutterViewController
+    self.setFrame(windowFrame, display: true)
+
+    RegisterGeneratedPlugins(registry: flutterViewController)
+
+    super.awakeFromNib()
+  }
+}