📦 array.prototype.flatmap

array.prototype.flatmap provides a polyfill for the flatMap method, which exists natively in modern JavaScript environments. This method combines the functionality of map and flat in a single step, transforming each element of an array using a mapping function, and then flattening the result into a new array. This simplifies code that requires both mapping and flattening, enhancing readability and performance. It is especially beneficial when dealing with nested arrays or data structures that need to be processed in a chained manner.