Add CommandRun implementation for executing batch commands

internal/batch/command.go

@@ -0,0 +1,23 @@
+package batch
+
+import (
+	"fmt"
+
+	"git.kor-elf.net/kor-elf-shield/go-nftables-client/contract"
+	"git.kor-elf.net/kor-elf-shield/go-nftables-client/internal/pkg"
+)
+
+type commandRun struct {
+	file *pkg.File
+}
+
+func NewCommand(file *pkg.File) contract.CommandRun {
+	return &commandRun{
+		file: file,
+	}
+}
+
+func (c *commandRun) Run(args ...string) error {
+	_, err := c.file.Write([]byte(fmt.Sprintf("%s\n", args)))
+	return err
+}