fix(anilist): decode array-shaped airingSchedule/relations and isolate per-service sync errors

The 1.6.1 fix exposed a latent decoding bug: AniList returns
airingSchedule.nodes and relations.nodes as arrays, but the Go Media
struct declared Nodes as single structs. Every full-media response
failed json.Unmarshal partway through - the update path turned that
into a rejected promise which skipped the MAL and Simkl syncs and all
table updates, while page loads silently continued with partially
decoded data (the reason the old tags/genres copy workaround existed).

- Media.AiringSchedule.Nodes is now []AiringScheduleNode and
  Media.Relations is an exported []MediaRelation (previously an
  unexported field silently dropped by encoding/json); title and
  fuzzy-date sub-structs promoted to named types.
- Regenerate wailsjs models for the new shapes.
- Anime.svelte: handleSubmit and deleteEntries now wrap each service
  in its own try/catch surfaced via setApiError/ErrorModal, so one
  service failing can no longer skip the others; removed the obsolete
  tags/genres copy workaround.
- AniListUpdateEntry/AniListDeleteEntry log HTTP status and response
  body on failure for terminal diagnostics.

Bump productVersion to 1.6.2.

AniListFunctions.go

@@ -726,17 +726,19 @@ func (a *App) AniListUpdateEntry(updateBody AniListUpdateVariables) (AniListGetS
 		return AniListGetSingleAnime{}, fmt.Errorf("AniList API error: %s", badPost.Errors[0].Message)
 	}
 	if status != "200 OK" {
+		log.Printf("AniListUpdateEntry failed with status: %s, body: %s\n", status, string(returnedBody))
 		return AniListGetSingleAnime{}, fmt.Errorf("API request failed with status: %s", status)
 	}
 
 	var returnedJson AniListUpdateReturn
 	err := json.Unmarshal(returnedBody, &returnedJson)
 	if err != nil {
-		log.Printf("Failed at unmarshal, %s\n", err)
+		log.Printf("AniListUpdateEntry failed to unmarshal response: %s, body: %s\n", err, string(returnedBody))
 		return AniListGetSingleAnime{}, fmt.Errorf("failed to parse AniList update response")
 	}
 
 	if returnedJson.Data.SaveMediaListEntry.MediaID == 0 {
+		log.Printf("AniListUpdateEntry returned no saved entry, body: %s\n", string(returnedBody))
 		return AniListGetSingleAnime{}, fmt.Errorf("AniList returned no saved entry")
 	}
 
@@ -795,6 +797,7 @@ func (a *App) AniListDeleteEntry(mediaListId int) (DeleteAniListReturn, error) {
 		return DeleteAniListReturn{}, fmt.Errorf("AniList API error: %s", badPost.Errors[0].Message)
 	}
 	if status != "200 OK" {
+		log.Printf("AniListDeleteEntry failed with status: %s, body: %s\n", status, string(returnedBody))
 		return DeleteAniListReturn{}, fmt.Errorf("API request failed with status: %s", status)
 	}