Initial commit: RustDesk 1.4.7 macOS desktop port

- Filled empty libs/hbb_common/ submodule (cloned from rustdesk/hbb_common)
- Patched Flutter 3.44 / Dart 3.12 compatibility:
  * flutter/lib/generated_bridge.dart: asTypedList with cast<>, DartPort=Int64
  * flutter/lib/common.dart: DialogTheme->DialogThemeData, TabBarTheme->TabBarThemeData
  * flutter/pubspec.yaml: extended_text 14.0.0->15.0.2, google_fonts override 5.0.0
  * flutter/macos/Runner/Configs/Release.xcconfig: EXCLUDED_ARCHS=x86_64
- Build verified: cargo check + cargo build --features flutter + cargo build --release --features flutter
- Verified flutter build macos --debug and --release both produce working .app
- Verified .dmg installer (27MB arm64) created via hdiutil
- Build deps: Xcode 26.5, CocoaPods 1.16.2, Flutter 3.44, VCPKG arm64-osx

flutter/lib/native/common.dart

@@ -0,0 +1,17 @@
+import 'dart:io';
+
+final isAndroid_ = Platform.isAndroid;
+final isIOS_ = Platform.isIOS;
+final isWindows_ = Platform.isWindows;
+final isMacOS_ = Platform.isMacOS;
+final isLinux_ = Platform.isLinux;
+final isWeb_ = false;
+final isWebDesktop_ = false;
+
+final isDesktop_ = Platform.isWindows || Platform.isMacOS || Platform.isLinux;
+
+String get screenInfo_ => '';
+
+final isWebOnWindows_ = false;
+final isWebOnLinux_ = false;
+final isWebOnMacOS_ = false;

flutter/lib/native/custom_cursor.dart

@@ -0,0 +1,44 @@
+import 'package:flutter_custom_cursor/cursor_manager.dart'
+    as custom_cursor_manager;
+import 'package:flutter_custom_cursor/flutter_custom_cursor.dart';
+
+import 'package:flutter/foundation.dart';
+import 'package:flutter/services.dart';
+
+import 'package:flutter_hbb/models/model.dart';
+
+deleteCustomCursor(String key) =>
+    custom_cursor_manager.CursorManager.instance.deleteCursor(key);
+resetSystemCursor() {}
+
+MouseCursor buildCursorOfCache(
+    CursorModel cursor, double scale, CursorData? cache) {
+  if (cache == null) {
+    return MouseCursor.defer;
+  } else {
+    final key = cache.updateGetKey(scale);
+    if (!cursor.cachedKeys.contains(key)) {
+      // data should be checked here, because it may be changed after `updateGetKey()`
+      final data = cache.data;
+      if (data == null) {
+        return MouseCursor.defer;
+      }
+      debugPrint(
+          "Register custom cursor with key $key (${cache.hotx},${cache.hoty})");
+      // [Safety]
+      // It's ok to call async registerCursor in current synchronous context,
+      // because activating the cursor is also an async call and will always
+      // be executed after this.
+      custom_cursor_manager.CursorManager.instance
+          .registerCursor(custom_cursor_manager.CursorData()
+            ..name = key
+            ..buffer = data
+            ..width = (cache.width * cache.scale).toInt()
+            ..height = (cache.height * cache.scale).toInt()
+            ..hotX = cache.hotx
+            ..hotY = cache.hoty);
+      cursor.addKey(key);
+    }
+    return FlutterCustomMemoryImageCursor(key: key);
+  }
+}

flutter/lib/native/win32.dart

@@ -0,0 +1,41 @@
+import 'dart:ffi' hide Size;
+
+import 'package:ffi/ffi.dart';
+
+import 'package:win32/win32.dart' as win32;
+
+/// Get windows target build number.
+///
+/// [Note]
+/// Please use this function wrapped with `Platform.isWindows`.
+int getWindowsTargetBuildNumber_() {
+  final rtlGetVersion = DynamicLibrary.open('ntdll.dll').lookupFunction<
+      Void Function(Pointer<win32.OSVERSIONINFOEX>),
+      void Function(Pointer<win32.OSVERSIONINFOEX>)>('RtlGetVersion');
+  final osVersionInfo = _getOSVERSIONINFOEXPointer();
+  rtlGetVersion(osVersionInfo);
+  int buildNumber = osVersionInfo.ref.dwBuildNumber;
+  calloc.free(osVersionInfo);
+  return buildNumber;
+}
+
+/// Get Windows OS version pointer
+///
+/// [Note]
+/// Please use this function wrapped with `Platform.isWindows`.
+Pointer<win32.OSVERSIONINFOEX> _getOSVERSIONINFOEXPointer() {
+  final pointer = calloc<win32.OSVERSIONINFOEX>();
+  pointer.ref
+    ..dwOSVersionInfoSize = sizeOf<win32.OSVERSIONINFOEX>()
+    ..dwBuildNumber = 0
+    ..dwMajorVersion = 0
+    ..dwMinorVersion = 0
+    ..dwPlatformId = 0
+    ..szCSDVersion = ''
+    ..wServicePackMajor = 0
+    ..wServicePackMinor = 0
+    ..wSuiteMask = 0
+    ..wProductType = 0
+    ..wReserved = 0;
+  return pointer;
+}