Insert and Update without Select

[tp971]

It seems like it is not possible to insert, update, or save an ActiveModel without selecting it. This can be an issue for big entities (e.g. models with potentially very big BLOBs). It is currently possible using Entity::insert_many and Entity::update_many, but 1. it is kinda unintuitive and 2. these don't trigger the methods in ActiveModelBehavior.

My idea would be implementing methods like ActiveModelTrait::do_{save,insert_update} that do not return the Model, but return an InsertResult or UpdateResult (similar methods could be added to EntityTrait).