QUICKFIX: Coordinate Mediation V3

Coordinate Mediation Enhancements

This PR implements some minor refactoring and best practices with respect to the did-comm protocol (specifically coordinate mediation)

The PR:

[x] FIX: correctly exports the coordinate mediation manager v3 from the package (and addresses naming conflicts with v2 exports)
[x] ensures consistent naming for differentiation of Version 2 Coordinate Mediation Specification and Version 3
[x] introduces better error handling on the mediate cli (directs to setup instructions in mediation agent)
[x] updates the mediation-manager README for more descriptive instructions on setup (both programatically and through the agent.yml)
[x] adds documentation/notes in code for easier consumption by developers

Check all that apply:

[X] I want these changes to be integrated
[x] I successfully ran pnpm i, pnpm build, pnpm test, pnpm test:browser locally.
[x] I allow my PR to be updated by the reviewers (to speed up the review process).
[ ] I added unit tests.
[ ] I added integration tests.
[ ] I did not add automated tests because _____, and I am aware that a PR without tests will likely get rejected.