Add static registry authentication

[Ruixey]

Is your feature request related to a problem? Please describe. It is currently (to my knowledge) only possible to supply authentication credentials for the registry to the ui via a secrets service that has to be installed on the target system.

Describe the solution you'd like It would be nice to have an option to supply static credentials for the registry via, for example, env variables.

Describe alternatives you've considered Other docker-based registry viewers are not as simple to setup/use.

Additional context This solution would be a great addition. It makes sense to have a read-only registry user assigned to the UI that allows everyone to browse the registry.

[Joxit]

Hi, I think what you're trying to do is the use of the configuration NGINX_PROXY_PASS_HEADER_* as stated in the README:

• NGINX_PROXY_PASS_HEADER_*: Update the default Nginx configuration and forward custom headers to your backend docker registry via environment variable and file (/etc/nginx/.env). Only when NGINX_PROXY_PASS_URL is used (see #206). Since 2.1.0

Check the linked issue, there is the example with NGINX_PROXY_PASS_HEARER_Authorization