## Description Extend the GraphQL `artworks` query with an optional search argument. Support case-insensitive search across artwork titles and artist names throughout the full dataset. ## Done when - [x] Search matches artwork titles and artist names regardless of letter case. - [x] Empty or whitespace-only input is treated as no search. - [x] Search is applied before pagination. - [x] `totalCount` reflects all matching artworks before pagination. - [x] Searches without matches return an empty list and `totalCount: 0`. - [x] Results have a stable order across pages. - [x] API tests cover search, empty results and pagination.