Document operation with the query scheduler. (#4100)
Document operation with the query scheduler. (#4100)

* Support Cortex Frontend V2.

* Format code.

* Start query scheduler in Docker compose.

* Model query flow in sequence diagram.

* Model calls to downstreamer.

* Move diagram to docs.

* Embed generated SVG.

* Descripe calls.

* Launch Cortex query scheduler.

* Disable sharding for now.

* Log which framework is used.

* Configure querier to use scheduler.

* Remove unwanted docs.

* Enable query splitting again.

* Document scheduler address.

* Document new scheduler options for frontend as well.

* Document operation with the query scheduler.

* Replace Cortex with Loki image.

* Remove unused Corte config.

* Correct merger errors.

* Clear up confusing sentence.

* Update docs/sources/operations/scalability.md

Co-authored-by: Karen Miller <ef8557dee2454782e1ca8165e06aa3aaae92367b@users.noreply.github.com>

Co-authored-by: Karen Miller <ef8557dee2454782e1ca8165e06aa3aaae92367b@users.noreply.github.com>
grafana/loki,grafana/loki,grafana/loki,grafana/loki,grafana/loki,grafana/loki