[ENH] - Consider using `oauth2proxy` instead of `jhsingle-native-proxy`

[aktech]

Feature description

Consider moving to oauth2proxy from jhsingle-native-proxy.

https://github.com/oauth2-proxy/oauth2-proxy

Value and/or benefit

• jhsingle-native-proxy is not maintained
• there are lot of unknowns and it's hard to debug proxy issues
• Error logging is difficult at the moment

Anything else?

No response