## Description Add an optional artist filter to the GraphQL `artworks` query. Filtering must work together with search and pagination. Provide artist options without requiring the frontend to download the entire artwork catalogue. ## Done when - [x] Artworks can be filtered by a selected artist. - [x] Artist filtering and search can be combined. - [x] Filtering is applied before pagination. - [x] `totalCount` uses the same conditions as the returned results. - [x] Omitting the artist filter returns results from all artists. - [x] Artist options are retrieved from the database through a bounded or paginated query. - [x] API tests cover filtering alone and combined with search.