Regira Events (front-end)

@regira/modules/events — a lightweight event mixin: an Event value object and an EventHandler whose injectInto(target) adds a trigger / on / once / off API to any object or prototype — for a service or manager that has to broadcast state changes to code holding no reference to it.

What it provides

Export	Purpose
EventHandler.injectInto(target)	Add listeners/on/once/off/trigger to an object or prototype.
on(key, …, callback)	Subscribe; space-separate keys, "" is a wildcard; returns the target (chainable).
once(key, …, callback)	Subscribe once; auto-removes after the first matching fire.
off(key, listener?)	Unsubscribe one callback, or all for key when listener is omitted.
trigger(event, arg?)	Fire by Event or string; async, runs listeners sequentially, returns Promise<unknown[]>.
Event	Value object: new Event(type, src?, data?) — data keys are copied onto the event.