event

type Bus interface {
	// Watch registers cb for events named name.
	Watch(name string, cb Callback)
	// Unwatch removes a previously registered cb.
	Unwatch(name string, cb Callback)
	// Dispatch delivers e to all callbacks watching its name.
	Dispatch(e *Event)
}

type Callback func(*Event)

type Event struct {
	Name string
	Data any
}

type Queue interface {
	// Push appends an event, dropping the oldest when capacity is exceeded.
	Push(e *Event)
	// Dump returns a snapshot of the buffered events.
	Dump() []*Event
}