Move all model class items from ACTION files to shared/models.py

[JordoHeffernan]

As a secureli contributor, I want shared models to be located in a central location

AC

1. Create a new file called shared_models.py in the shared directory (if it doesn't already exist)
2. Move any model classes that exist at the top of files in the actions directory to the new file IF they are reused in multiple files
   a. models that are only used in the file in which they're defined should be left as is.
3. Update any and all dependent imports (VS code should do this for you)

Notes

• working branch to split off of: refactor/secureli-000-modular-refactor