Image scrapers should be able to return a `Galleries` field

Describe the feature you'd like

Scene scrapers can return groups that the scene belongs to: https://docs.stashapp.cc/in-app-manual/scraping/scraperdevelopment/#scene. However, image scrapers cannot return galleries that the image belongs to: https://docs.stashapp.cc/in-app-manual/scraping/scraperdevelopment/#image.

Image scrapers should be able to return a Galleries field.

Describe the benefits this would bring to existing users

Image scrapers could automatically create galleries or add images to existing galleries based on scraped data. For example, individual images saved from Imgur or Reddit galleries could be put into a Stash gallery even though they might've not been saved as a separate directory.

Is there an existing way to achieve this goal?

Not as far as I know.

Have you searched for an existing open/closed issue?

• I have searched for existing issues and none cover the core request of my proposal

Additional context

No response