[Lens] Client side caching

[flash1293]

Currently Lens fetches new data on every configuration change, even if it's just visualization related. This is caused by the general architecture of Lens: Data fetching and rendering is done via expression and for every change the expression has to be run again which includes the esaggs function triggering an Elasticsearch request.

To improve response times for these kinds of changes, the data should be cached in the browser to avoid the additional round trip time of fetching data from the server.

Requirements:

• Cache should be tied to the session id in some way - it's already controlled and reset in the right situations
• To maximize cache hits (which should minimize total loading time), the request should be served from cache even if the expression args change (e.g. for labels), as long as the request itself doesn't change (stringified request is probably a good cache key)
• A cache miss doesn't have a large impact, it's not necessary for the cache to survive browser refreshes or similar (can be occasionally unexpectedly reset due to external situations, e.g. too much cached data)
• The cache doesn't have to be large, holding ~10 request/responses is good enough
• It's likely the same request is submitted multiple times in a very short time frame (while the previous request is still in flight) - the cache should be able to handle this without failing (de-duping the request would be nice, but wouldn't have a large impact)
• Not necessary for first iteration, but due to the user flow between dashboard and Lens, it would be helpful to be able to share the cache between apps so data doesn't have to be re-fetched after returning to the dashboard from editing a chart.

[elasticmachine]

Pinging @elastic/kibana-app (Team:KibanaApp)

[flash1293]

cc @ppisljar @lukasolson

[flash1293]

Requirements are met by #92439, closing this