Enable new fields in database to backend

Update the backend API to expose additional fields that may be needed for enhanced functionality in the Octopets application.

Context
The current backend API provides basic listing and review endpoints. As the application evolves, there may be a need to expose additional fields from the data models to support new features in the frontend.

Tasks

- [ ] - Review existing data models (Listing.cs, Review.cs) for fields that aren't currently exposed
- [ ] - Identify which additional fields should be included in API responses
- [ ] - Update repository interfaces and implementations if needed
- [ ] - Update endpoint responses to include new fields
- [ ] - Test API endpoints to verify new fields are returned correctly
- [ ] - Update OpenAPI documentation to reflect the changes

Start by reviewing Listing.cs and Review.cs, then compare their fields with the current listing and review endpoint responses. Inspect the repository interfaces and implementations before deciding which fields are missing; the work is done when the selected fields appear correctly in API responses, endpoint tests pass, and the OpenAPI documentation reflects them.

Written by the indexing model from the issue text.