fix(backend): 修复上传转码与短剧发布链路（multipart 上限、转码防重、剧集发布、schema 字段）

fruitshorts-module-media/src/main/java/com/fruitshorts/media/service/TranscodeService.java

@@ -39,11 +39,11 @@ public class TranscodeService {
     private final TranscodeTaskMapper transcodeTaskMapper;
     private final MediaRenditionMapper mediaRenditionMapper;
 
-    /** 上传完成后入队；同一剧集重复入队时复用未完成的任务，避免重复转码。 */
+    /** 上传完成后入队；同一媒资重复入队时复用未完成的任务，避免重复转码。 */
     @Transactional(rollbackFor = Exception.class)
     public Long enqueue(Long mediaAssetId, Long dramaId, Long episodeId, String sourceUrl) {
         TranscodeTask existing = transcodeTaskMapper.selectOne(Wrappers.<TranscodeTask>lambdaQuery()
-                .eq(TranscodeTask::getEpisodeId, episodeId)
+                .eq(TranscodeTask::getMediaAssetId, mediaAssetId)
                 .in(TranscodeTask::getStatus, List.of(STATUS_QUEUED, STATUS_RUNNING))
                 .last("limit 1"));
         if (existing != null) {