feat: update button (download, verify, stage)

cmd/server/main.go

@@ -50,7 +50,13 @@ var envDefaults = map[string]string{
 	"UPDATE_FEED_URL":                "https://git.floriansylvain.fr",
 }
 
+const versionFlag = "--version"
+
 func main() {
+	if len(os.Args) == 2 && os.Args[1] == versionFlag {
+		fmt.Println(version)
+		return
+	}
 	if err := run(); err != nil {
 		log.Fatal(err)
 	}