Recap - Simple Event Handler

Write a function createEventSystem that creates a simple event system with pre-registered events and triggers one based on input parameters.

Logic:

• Create an empty table to store events inside createEventSystem
• Define a register function that takes eventName and callback (a function to run later, when the event is triggered), storing the callback in the events table with the event name as the key
• Define a trigger function that takes eventName and arg, looks up the callback in the events table, and calls it with the argument if it exists
• Before triggering anything, register these three events:
  • "double": takes a number and returns it multiplied by 2
  • "square": takes a number and returns it squared
  • "increment": takes a number and returns it plus 1
• Trigger the event specified by the eventName parameter with the value parameter
• Return the result of the triggered event, or "Event not found" if the event doesn't exist

Parameters:

• eventName (string): The name of the event to trigger
• value (number): The value to pass to the event callback

Returns:

• The result of the callback function (number), or "Event not found" if the event doesn't exist (number|string)