Refactor: extract Linux/macOS client shared code into common

macos/uninstall.sh

@@ -7,11 +7,11 @@ echo "=== GhostClient 卸载程序 ==="
 echo ""
 
 # 1. 停止进程
-echo "[1/3] 停止进程..."
+echo "[1/4] 停止进程..."
 pkill -9 -f "$APP_DIR" 2>/dev/null || true
 
 # 2. 删除文件
-echo "[2/3] 删除文件..."
+echo "[2/4] 删除文件..."
 sudo rm -rf "$APP_DIR"
 rm -rf ~/.config/ghost 2>/dev/null || true
 rm -f /tmp/ghost.log 2>/dev/null || true