chore(docs): documentation for extending session data with provider functions

[halvaradop]

☕️ Reasoning

This pull request adds documentation for extending session data using provider functions in the configuration file. It explains how to use the authorize and profile functions provided by authentication providers to customize the user object stored in the session.

🧢 Checklist

• [x] Documentation
• [ ] Tests
• [x] Ready to be merged

📌 Resources

• Security guidelines
• Contributing guidelines
• Code of conduct
• Contributing to Open Source

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Name	Status	Preview	Comments	Updated (UTC)
auth-docs	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Jul 27, 2024 10:16pm

1 Skipped Deployment

Name	Status	Preview	Comments	Updated (UTC)
next-auth-docs	⬜️ Ignored (Inspect)	Visit Preview		Jul 27, 2024 10:16pm

[vercel[bot]]

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[halvaradop]

I have followed your instructions and moved the content