21118: Adds warnings to train and set_feature_attributes about violated feature bounds

[cademack]

Adds warnings in two situations:

1. When new cases are trained that contain values which violate boundaries set in the feature attributes.
2. When feature attributes are set with boundaries that are violated by existing cases.

Also mildly refactors #train by moving a lot of the post-train logic into a new private helper method.

[howsoRes]

change this code and the one below to be:

(first (contained_entities
    (list (query_exists feature) (query_min feature 1))
))