retrieve
Retrieves a Flow of Lists containing all Image objects from the database.
This method delegates the retrieval to the imageDAO using its selectImagesWithGeoLocationAndAdministrativeUnitName
method. The retrieved data might contain additional information about GeoLocation and AdministrativeUnitName (depending on the DAO implementation).
This method then extracts and returns a Flow of Lists containing just the Image objects (potentially after filtering or transforming the retrieved data using toImages()).
Return
a Flow that emits Lists of Image objects.