Expose more query languages in Kibana as additional data sources

[stacey-gammon]

Elasticsearch exposes a SQL endpoint, EQL is coming soon, and possibly PromQL as well. Kibana needs a way to expose these query languages to users.

We will not be adding these languages as additional options in the query bar.
transformative query languages do not make sense there because of their ability to change the data shape through aggregations.

We will be working on adding these languages as additional data sources, however. These data sources may appear:

• In Canvas
• In Lens
• In Discover
• In SIEM Timeline & detection anomaly builder
• In Observability

We will likely start by adding eseql expression functions in Canvas, and adding more search strategies that solution developers can use to expose additional query options. Getting this exposed in Lens is on the longer term roadmap.

Once again though, this will not be exposed through our query bar because of the way these things work together on a dashboard. The query bar should only be used for narrowing data, never changing data.

[elasticmachine]

Pinging @elastic/kibana-app-arch (Team:AppArch)

[lukasolson]

Closing in favor of #126095 (specifically #127252).