add out-of-the-box support for external authentication with OIDC/OAuth

Hello,

I tried using the tool but there is no support for external authentication system, like OIDC.

I found there are some plugins https://github.com/apache/answer-plugins
including an OAuth 2 plugin https://github.com/apache/answer-plugins/tree/main/connector-basic

I've tried using the plugin but it doesn't work.
plugins can only be used by making a custom build of apache answer.
I've tried that but I hit successive errors, with needing firewall access to go to github, then needing go 1.22.x to run, then some error in PNPM, that needed to have exactly pnpm 1.10 to pass, then error in NPM and finally some javascript install scripts.

At this point I gave up.
I'm sorry to say but the tool is not usable without support for authentication out-of-the-box.

Could you consider including auth support in the app?

# A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

apache answer has no support for external authentication out of the box.

## Is your enhancement request related to a problem? Please describe

apache answer has no support for external authentication out of the box.

## Describe the solution you'd like

OIDC/OAuth authentication support out of the box.

## Describe alternatives you've considered

tried the plugin, doesn't work

Beginnen Sie mit der Überprüfung des vorhandenen OAuth 2-Plugins in apache/answer-plugins, insbesondere von connector-basic, sowie der Authentifizierungs-Einstiegspunkte in Apache Answer. Ermitteln Sie die Integrations- und Build-Anforderungen für einen sofort einsatzbereiten OIDC/OAuth-Flow; als abgeschlossen gilt die Arbeit, wenn die externe Authentifizierung ohne benutzerdefinierten Build oder die Installation eines Plugins funktioniert.

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