Build a Typed Event Emitter

The Emitter below works, but its handlers and payloads are any: nothing checks that "login" carries a { user }, and a typo in an event name goes unnoticed.

Make it generic: Emitter<Events extends object>. The event name is K extends keyof Events, and the payload is Events[K] in both on and emit. Keep the AppEvents map. Remove any.

What Check tests

Your code has no type errors
The console prints hello Asha and items 2
A correct payload is accepted
A misspelled event name is rejected
A wrong payload type is rejected
A handler parameter is typed from the event name
No any

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Build a Typed Event Emitter