fix: update remote system detection command for Windows compatibility

The current Windows system detection uses a simple `ver` command which fails on Windows servers where PowerShell is configured as the default SSH shell. The `ver` command is only available in CMD, not in PowerShell, causing system detection to fail incorrectly.

Author: MrHIDEn

plugin.go

@@ -147,7 +147,7 @@ func (p *Plugin) removeAllDestFile() error {
 			},
 		}
 
-		_, _, _, err := ssh.Run("ver", p.Config.CommandTimeout)
+		_, _, _, err := ssh.Run("cmd /c ver 2>$null", p.Config.CommandTimeout)
 		systemType := "unix"
 		if err == nil {
 			systemType = "windows"
@@ -292,7 +292,7 @@ func (p *Plugin) Exec() error {
 			}
 
 			systemType := "unix"
-			_, _, _, err := ssh.Run("ver", p.Config.CommandTimeout)
+			_, _, _, err := ssh.Run("cmd /c ver 2>$null", p.Config.CommandTimeout)
 			if err == nil {
 				systemType = "windows"
 			}

plugin_test.go

@@ -571,7 +571,7 @@ func TestRemoveDestFile(t *testing.T) {
 		DestFile: "/etc/resolv.conf",
 	}
 
-	_, _, _, err := ssh.Run("ver", plugin.Config.CommandTimeout)
+	_, _, _, err := ssh.Run("cmd /c ver 2>$null", plugin.Config.CommandTimeout)
 	systemType := "unix"
 	if err == nil {
 		systemType = "windows"