SearchKit - Fix support for non-DAO entities

[colemanw]

Overview

Fixes SearchKit to work with more entities.

Before

SearchKit would crash if running a search on a non-DAO entity (Extension, Entity, Afform, etc)

After

Works, test added

Technical Details

Had to remove assumptions about the entity params supporting join and having, a well as reliance on the Api4SelectQuery object.

[civibot]

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