Implement a function memoize(fn) that returns a memoized version of the given function.

The function should:

• Accept a function fn that can take any number of arguments.
• Cache the results of previous calls based on the arguments.
• Return the cached result if the function is called again with the same arguments.
• Work for primitive arguments and arrays (use JSON.stringify for cache key generation).

Example

function add(a, b) {
  console.log("computing...");
  return a + b;
}

const memoizedAdd = memoize(add);
memoizedAdd(1, 2); // "computing..." 3
memoizedAdd(1, 2); // 3, retrieved from cache