OptionalactionThe method to call when module is a class/factory instance (defaults to handle).
OptionalisWhether module is a class to resolve.
OptionalisWhether module is a factory to resolve.
The key this handler answers (job name, event name, command name, route key…).
The handler: a function, an instance, a class or a factory.
A handler meta-module for imperative registration (mirrors the framework's
{ module, isClass?, isFactory? }meta-module shape, plus the routingkeyand optionalaction).