Add: Server variables are opt-out by default

- Pull the Nushell and Deno versions from the server.
- Support downloading Nushell and Deno from a url (not GitHUb).
- Add support for nu config.nu and env.nu files.
- Add support for default Deno permissions.

main.go

@@ -117,10 +117,10 @@ func main() {
 		fmt.Println(a.PublicIP())
 	case "getpython":
 		a.GetPython(true)
-	case "getdeno":
-		a.GetDeno(true)
-	case "getnushell":
-		a.GetNushell(true)
+	case "installdeno":
+		a.InstallDeno(true)
+	case "installnushell":
+		a.InstallNushell(true)
 	case "runmigrations":
 		a.RunMigrations()
 	case "recovermesh":