Add proposal for registry auth

[eleftherias]

Ref #2962

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.01%. Comparing base (5cdb41f) to head (6547384).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2964   +/-   ##
=======================================
  Coverage   56.00%   56.01%           
=======================================
  Files         328      328           
  Lines       32290    32290           
=======================================
+ Hits        18084    18086    +2     
+ Misses      12670    12668    -2     
  Partials     1536     1536           

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[JAORMX]

What about the registry returning a 401 with an indicator of authentication parameters? Similar to what MCP servers do and what we did in Minder.

As an option, I mean.