Install command batches through one path

builtins.go

@@ -29,7 +29,7 @@ type versionDocument struct {
 	Revision string `yaml:"revision"`
 }
 
-func (a *App) installBuiltins() error {
+func (a *App) builtinCommands() []Command {
 	help := captureCommand(CommandSpec[helpInput]{
 		Name:        "help",
 		Summary:     "Show help for commands.",
@@ -61,9 +61,7 @@ func (a *App) installBuiltins() error {
 			return renderVersionOutcome(identity, input.Format, invocation.Streams)
 		},
 	})
-	a.commands["help"] = &commandNode{command: help, reserved: true}
-	a.commands["version"] = &commandNode{command: version, reserved: true}
-	return nil
+	return []Command{help, version}
 }
 
 func parseVersionScope(value string) (string, error) {