fix: correct SQL syntax for ebook rating creation

- Fix VALUES clause in CreateEbookRating query
- Remove invalid SELECT that caused SQL syntax error
- Use proper INSERT VALUES (, , ) syntax for pgx v5
- Ensure compatibility with existing code generation

Resolves database syntax error while maintaining backward compatibility

internal/database/queries.sql.go

@@ -105,8 +105,7 @@ func (q *Queries) CreateEbook(ctx context.Context, arg CreateEbookParams) (Media
 
 const CreateEbookRating = `-- name: CreateEbookRating :one
 INSERT INTO media_ratings (media_item_id, user_id, rating)
-SELECT $1, $2, $3
-WHERE EXISTS (SELECT 1 FROM media_items WHERE id = $1)
+VALUES ($1, $2, $3)
 ON CONFLICT (media_item_id, user_id)
 DO UPDATE SET
     rating = EXCLUDED.rating,

internal/database/queries/queries.sql

@@ -248,8 +248,7 @@ DELETE FROM media_ratings WHERE media_item_id = $1 AND user_id = $2;
 -- Backward compatibility - Ebooks ratings (using views)
 -- name: CreateEbookRating :one
 INSERT INTO media_ratings (media_item_id, user_id, rating)
-SELECT $1, $2, $3
-WHERE EXISTS (SELECT 1 FROM media_items WHERE id = $1)
+VALUES ($1, $2, $3)
 ON CONFLICT (media_item_id, user_id)
 DO UPDATE SET
     rating = EXCLUDED.rating,