Update link to Edge Docs in README.md

[mattmazzola]

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Description

The previous link to Edge Docs at https://edge.radapp.io was incorrect, perhaps become stale.

Correct link is https://edge.docs.radapp.io , found from this page

Auto-generated description

🤖 Generated by Copilot at ea922b9

Summary

🌐🛠️🙌

Fix broken and inconsistent links in README.md. Update edge docs link to use new domain name and code of conduct link to use proper case.

The README had links that were broken
Or not very friendly when spoken
So they changed the domain
And the case to maintain
A standard of quality unwoken

Walkthrough

• Update the link to the edge docs to use the correct domain name (link in README.md). This fixes a broken link and improves the user experience of accessing the edge docs.

Issue reference

[AaronCrawfis]

Thanks for the fix!