feat(cmd): add version subcommand with ldflag-injected build info

cmd/archduino/main.go

@@ -38,7 +38,11 @@ import (
 	"gitlab.hive-brain.de/MDietermann/Archduino/internal/tui/wizard"
 )
 
-var version = "dev"
+var (
+	version = "dev"
+	commit  = "none"
+	date    = "unknown"
+)
 
 // buildRegistry constructs a module registry populated with all Plan 3a
 // modules, wired against the provided config and platform dependencies.
@@ -85,6 +89,7 @@ func main() {
 	root.AddCommand(newThemeCmd())
 	root.AddCommand(newNewCmd())
 	root.AddCommand(newDoctorCmd())
+	root.AddCommand(newVersionCmd())
 
 	// Wire SIGINT/SIGTERM to a cancellable context so long-running phases
 	// (engine.Run, sudo keepalive) observe the cancellation promptly.
@@ -422,3 +427,13 @@ func newDoctorCmd() *cobra.Command {
 	cmd.Flags().StringVar(&overlayPath, "overlay", "", "path to overlay.yaml")
 	return cmd
 }
+
+func newVersionCmd() *cobra.Command {
+	return &cobra.Command{
+		Use:   "version",
+		Short: "Print version, commit, and build date",
+		Run: func(cmd *cobra.Command, args []string) {
+			fmt.Printf("archduino %s\ncommit: %s\ndate:   %s\n", version, commit, date)
+		},
+	}
+}