Field statistics aren't supported with ES|QL #3027
Description
Since 8.17 elastic/kibana#222974, field statistics support was removed in a few instances:
- it's no longer possible to add a field statistics panel to a dashboard
- the field statistics tab is no longer present in Discover in ES|QL mode. It's still there in KQL mode.
- There's also some impact on the ML Data Visualizer side but nothing that I could find in the docs to change