feat(backend): add genres support to AniList integration

Add the `genres` field to AniList GraphQL queries and type definitions:
- Add genres field to GetAniListItem query for fetching single anime details
- Add genres field to AniListSearch query for search results
- Add genres field to GetAniListUserWatchingList query for user's watch list
- Update MediaList type definition to include Genres []string field

This enhancement allows the application to retrieve and display anime genre
information from the AniList API, providing users with better categorization
and discovery capabilities.

AniListTypes.go

@@ -74,7 +74,8 @@ type MediaList struct {
 			TimeUntilAiring int `json:"timeUntilAiring"`
 			Episode         int `json:"episode"`
 		} `json:"nextAiringEpisode"`
-		Tags []struct {
+		Genres []string `json:"genres"`
+		Tags   []struct {
 			Id             int    `json:"id"`
 			Name           string `json:"name"`
 			Description    string `json:"description"`