Consider adding audit trails to additional models

Touchpoints uses [PaperTrail](https://github.com/paper-trail-gem/paper_trail) to audit changes to:

- digital products
- digital service accounts
- personas
- services
- websites

This helps answer questions about who changed what and when.

Consider whether we should be auditing additional models - forms, in particular.

Review how PaperTrail currently audits digital products, digital service accounts, personas, services, and websites, then assess whether forms or other models should be included. Done means reaching a decision about which additional models, if any, should receive audit trails.

Written by the indexing model from the issue text.