Implement a debounce function

Problem: Implement debounce(fn, wait)

Implement a debounce utility function.

Behavior

Given a function fn and a delay wait (milliseconds), debounce(fn, wait) returns a new function debounced such that:

• When debounced(...args) is called repeatedly, it postpones calling fn until after wait ms have elapsed since the most recent call.
• When the timer finally expires, fn is invoked once with the latest arguments and the original this context.

Requirements

• Preserve this binding when invoking fn .
• The returned function should be callable multiple times.

Optional extensions (if time)

• Support debounced.cancel() to cancel a pending invocation.
• Support debounced.flush() to immediately run the pending invocation (if any).