Proxy read ids from redis

[khanova]

Problem

Proxy doesn't know about existing endpoints.

Summary of changes

• Added caching of all available endpoints.
• On the high load, use it before going to cplane.
• Report metrics for the outcome.
• For rate limiter and credentials caching don't distinguish between -pooled and not

TODOs:

• Make metrics more meaningful
• Consider integrating it with the endpoint rate limiter
• Test it together with cplane in preview

Checklist before requesting a review

• I have performed a self-review of my code.
• If it is a core feature, I have added thorough tests.
• Do we need to implement analytics? if so did you add the relevant metrics to the dashboard?
• If this PR requires public announcement, mark it with /release-notes label and add several sentences in this section.

Checklist before merging

• Do not forget to reformat commit message to not include the above checklist

[github-actions]

2748 tests run: 2630 passed, 0 failed, 118 skipped (full report)

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Code coverage* (full report)

• functions: 28.0% (6428 of 22933 functions)
• lines: 46.7% (45108 of 96556 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
6b687a7 at 2024-04-09T17:57:55.376Z :recycle:}