Add shard request caching

[bryanlb]

Description

For requests that come through to a given shard that are identical to previous queries (think long-range queries, dashboarding, etc) these should use a request cache and not invoke Lucene. This is similar in concept to the shard request caching as described here https://www.elastic.co/blog/elasticsearch-caching-deep-dive-boosting-query-speed-one-cache-at-a-time but differs in techincal implementation due to our architecture.

A POC of this has been done here #714, but will need some additional considerations around how to handle the issue of extended bounds for date histograms, and any similar aggregation metadata fields. This POC did not perform as expected either, as the resulting queries did not see a significant speed improvements - we will need to add additional instrumentation for hit/miss ratios to ensure we are getting the expected hit ratios.

[github-actions]

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