Improve hook_entity_presave documentation

This commit updates the documentation for the Drupal API page to provide more clarity on accessing the original entity object in a multi-language context. It also suggests alternative methods for retrieving the original translation if $entity->original does not refer to the expected translation. This should help improve understanding for developers working with Drupal in a multi-language context.

Change definitely seems better then before.

But this phrase

* In such cases, you can use other available methods
* to retrieve the original translation.

Feel if we are going to mention that we should mention what those are or least where someone would go to look.

Rashmisoni → made their first commit to this issue’s fork.

Is this specific to hook_entity_presave or should we update it for hook_entity_update as well? Also note hook_ENTITY_TYPE_presave and hook_ENTITY_TYPE_update also mention $entity->original.

I'm also wondering if it's better to address this in 📌 Define 'original' as property on the entity object Needs work where the property is defined rather than in the hook documentation.