Docs: clarify cases where traditional functions are preferred

[Manvendra0023]

This PR adds a small clarification to the Arrow Functions section describing cases where traditional functions are still preferred, such as function hoisting, dynamic this binding, and use of the arguments object.

The goal is to improve clarity without changing the existing recommendation.

[ljharb]

Arrow functions should only be used for inline callbacks. Everything else should use normal functions.

[Manvendra0023]

Thanks for the clarification — that makes sense.

I agree that this guide should not encourage relying on hoisting, and that arrow functions should generally be preferred except for inline callbacks.

My intent here wasn’t to recommend hoisting as a practice, but to document why traditional functions still exist and what technical differences remain, for readers who may encounter them in real codebases.

I’m happy to remove or reword the hoisting mention to avoid implying it’s an acceptable pattern under this guide. Please let me know if you’d prefer the section to focus only on cases like named functions for debugging / stack traces, or if you’d rather drop the section entirely.