feat: add 'polecats' as alias for polecat command

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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

internal/cmd/polecat.go

@@ -27,7 +27,7 @@ var (
 
 var polecatCmd = &cobra.Command{
 	Use:     "polecat",
-	Aliases: []string{"cat"},
+	Aliases: []string{"cat", "polecats"},
 	Short:   "Manage polecats in rigs",
 	Long: `Manage polecat lifecycle in rigs.