Reorder models to eliminate string forward references

Reorder class definitions so dependencies are defined before dependents,
allowing converter helpers to reference actual classes instead of string
names. Setup is moved to the bottom since it references nearly every
other model.

The only remaining string forward reference is Place.sub_places which
is self-referential and unavoidable.

Also adds section comments to group models by domain: state/command
primitives, device/definition, execution/action groups, infrastructure,
configuration, and UI profiles.

Author: iMicknl