feat(cli): add test-email command to check mail capability

Added a new test-email CLI command that checks if the system has mail utilities
installed (mail, sendmail, msmtp). This command does not send an email but simply
verifies the availability of outbound mail capability on the server. Useful for
verifying mail setup without triggering any actual message.

Author: maheshbhatiya73

cmd/email/test_email.go

@@ -0,0 +1,41 @@
+package email
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+
+	"github.com/spf13/cobra"
+	"stackroost/internal/logger"
+)
+
+
+var TestEmailCmd = &cobra.Command{
+	Use:   "test-email",
+	Short: "Check if email capability is available on this system (mail/sendmail/msmtp)",
+	Run: func(cmd *cobra.Command, args []string) {
+		mailers := []string{"mail", "sendmail", "msmtp"}
+		found := false
+
+		for _, bin := range mailers {
+			_, err := exec.LookPath(bin)
+			if err == nil {
+				logger.Success(fmt.Sprintf("Mailer available: %s", bin))
+				found = true
+			}
+		}
+
+		if !found {
+			logger.Warn("No mail sending utilities found (mail/sendmail/msmtp)")
+			logger.Info("You can install one, e.g., `sudo apt install mailutils` or `sendmail`")
+			os.Exit(1)
+		}
+
+		logger.Info("Email sending capability appears to be available")
+	},
+}
+
+func init() {
+	TestEmailCmd.Flags().String("to", "", "Recipient email address")
+	TestEmailCmd.MarkFlagRequired("to")
+}

cmd/root.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 	"stackroost/cmd/ssl"
 	"stackroost/cmd/logs"
+	"stackroost/cmd/email"
 )
 
 var rootCmd = &cobra.Command{
@@ -211,7 +212,8 @@ func init() {
 	createDomainCmd.Flags().Bool("ssl", false, "Enable Let's Encrypt SSL (Apache/Nginx only)")
 	createDomainCmd.MarkFlagRequired("name")
 	rootCmd.AddCommand(ssl.CheckSSLExpiryCmd)
-		rootCmd.AddCommand(logs.AnalyzeTrafficCmd)
+	rootCmd.AddCommand(logs.AnalyzeTrafficCmd)
+	rootCmd.AddCommand(email.TestEmailCmd)
 }
 
 func Execute() {