feat(rendezvous): make /rendezvous/1.0.0/ public

[12TreeMan31]

Description

This PR exposes PROTOCOL_NAME, which contains the rendezvous protocol ID.

Unlike many other protocols, rendezvous does not currently provide its protocol ID to the public. Exposing PROTOCOL_NAME makes it more consistent.

closes: #6174

AI Assistance Disclosure

Tools used (required — write none if no AI was used): none

Attestation (required):

• I have read every line of this diff, understand what it does, and can explain it in review.

Notes & open questions

I did change PROTOCOL_IDENT to PROTOCOL_NAME because thats how other protocols named their ID's from what I've seen.

This is my first ever PR, I hope I did everything correct.

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• A changelog entry has been made in the appropriate crates