[Discover] Integration of ad-hoc data views

[kertal]

With the merge of #136251, we can now start to integrate ad-hoc data views in Discover.

There has been a follow up PR #136266, even if it's currently failing, showing how the basic integration will work technically.

For the initial support, #136266 , should be finished.
Parts of Discover, that do not currently support Ad hoc Data views should prompt users, when they continue beyond, the Ad-hoc data view will be persisted. This way we ensure, that all functionality of Discover in the initial state of integration can be used.

Here's an example how the prompt looked like in the POC of #113814

The wording of course has to be changed (Back in the days data views still were called index patterns).

Parts of Discover UI that won't support data views in the initial phase

• Visualize in Lens (Lens team is working on that, so it may already be possible)
• Visualize in Maps
• Alerts
• Share
• Saving
• Field statistics (high likely)

[elasticmachine]

Pinging @elastic/kibana-data-discovery (Team:DataDiscovery)