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

res/DEBIAN/postinst

@@ -0,0 +1,27 @@
+#!/bin/bash
+
+set -e
+
+if [ "$1" = configure ]; then
+
+	INITSYS=$(ls -al /proc/1/exe | awk -F' ' '{print $NF}' | awk -F'/' '{print $NF}')
+	ln -f -s /usr/share/rustdesk/rustdesk /usr/bin/rustdesk
+
+	if [ "systemd" == "$INITSYS" ]; then
+
+		if [ -e /etc/systemd/system/rustdesk.service ]; then
+			rm /etc/systemd/system/rustdesk.service /usr/lib/systemd/system/rustdesk.service /usr/lib/systemd/user/rustdesk.service >/dev/null  2>&1
+		fi
+		mkdir -p /usr/lib/systemd/system/
+		cp /usr/share/rustdesk/files/systemd/rustdesk.service /usr/lib/systemd/system/rustdesk.service
+		# try fix error in Ubuntu 18.04
+		# Failed to reload rustdesk.service: Unit rustdesk.service is not loaded properly: Exec format error.
+		# /usr/lib/systemd/system/rustdesk.service:10: Executable path is not absolute: pkill -f "rustdesk --"
+		if [ -e /usr/bin/pkill ]; then
+			sed -i "s|pkill|/usr/bin/pkill|g" /usr/lib/systemd/system/rustdesk.service
+		fi
+		systemctl daemon-reload
+		systemctl enable rustdesk
+		systemctl start rustdesk
+	fi
+fi