Feature: add option to fork someone's post (like repost)

[Dream-World-Coder]

[wangwangbobo]

Forking posts is a great way to encourage remixing and building on others' ideas!

Similar to GitHub's fork model:

• Creates a copy linked to the original
• Could show "forked from @author" attribution
• Original author gets notified when someone forks their post

This would boost engagement and content creation. 🍴