feat: Add basic Redis storage support

[ruhulio]

Description

Add basic Redis storage support that surfaces common settings and parameters.

There really wasn't any useful unit tests to add since the heavy lifting is all done by the underlying Redis client which when mocked is effectively testing almost nothing.

I did verify the functionality manually by running a local and remote Redis instance, e.g. docker run -p 6379:6379 -it redis:latest.

As KVStorage is a new feature with only a mention in the OAuthProxy documentation as part of client_storage, I wasn't sure where docs for a new implementation of the protocol should be added. Happy to add something if pointed to the appropriate spot.

Contributors Checklist

• My change closes Add Redis support for the KVStorage protocol #1896
• I have followed the repository's development workflow
• I have tested my changes manually and by adding relevant tests
• I have performed all required documentation updates

Review Checklist

• I have self-reviewed my changes
• My Pull Request is ready for review

---

[strawgate]

As mentioned in #1896 I'd like to fit this into the broader change we might be making to kv caches

[jlowin]

@ruhulio really appreciate this but going to close in favor of #1913 as we're abstracting all storage into another package!

[ruhulio]

@ruhulio really appreciate this but going to close in favor of #1913 as we're abstracting all storage into another package!

Yep, that works for me.