Docs for logged-out ID

[slowcooked99]

💸 TL;DR

Adds documentation about reading the logged-out ID in an app.

📜 Details

Gives a brief overview about the Reddit LOID and how to read it in the app Context. This feature is experimental and the docs are only under Next.

🧪 Testing Steps / Validation

Ran docs locally with yarn start, verified things look pretty. Eg:

✅ Checks

• CI tests (if present) are passing
• Adheres to code style for repo
• Contributor License Agreement (CLA) completed if not a Reddit employee