Build a method decorator that marks a method as the handler for a key, under a given metadata key.
Consuming modules use it to create their own named decorators, e.g.
export const OnJob = createKeyDecorator(QUEUE_KEY) -> @OnJob('send-email'). Each decorated
method appends { key, action } to the class's metadata under metaKey; the module later reads
them with collectKeyHandlers. Purely additive: it annotates, it does not wrap the method.
Build a method decorator that marks a method as the handler for a key, under a given metadata key.
Consuming modules use it to create their own named decorators, e.g.
export const OnJob = createKeyDecorator(QUEUE_KEY)->@OnJob('send-email'). Each decorated method appends{ key, action }to the class's metadata undermetaKey; the module later reads them with collectKeyHandlers. Purely additive: it annotates, it does not wrap the method.