feat(media): 支持后台转码配置与缩略图轴

sql/schema-phase1.sql

@@ -785,6 +785,32 @@ CREATE UNIQUE INDEX IF NOT EXISTS uk_rendition ON media_rendition (media_asset_i
 CREATE INDEX IF NOT EXISTS idx_rendition_episode ON media_rendition (episode_id);
 COMMENT ON TABLE media_rendition IS '多码率产物；播放票据按此生成 master playlist';
 
+CREATE TABLE IF NOT EXISTS media_thumbnail (
+  id             BIGINT PRIMARY KEY,
+  episode_id     BIGINT       NOT NULL,
+  drama_id       BIGINT       NOT NULL DEFAULT 0,
+  vtt_object_key VARCHAR(512) NOT NULL DEFAULT '',
+  sprite_prefix  VARCHAR(512) NOT NULL DEFAULT '',
+  interval_sec   INT          NOT NULL DEFAULT 1,
+  columns        INT          NOT NULL DEFAULT 10,
+  rows           INT          NOT NULL DEFAULT 1,
+  thumb_width    INT          NOT NULL DEFAULT 160,
+  thumb_height   INT          NOT NULL DEFAULT 0,
+  frame_count    INT          NOT NULL DEFAULT 0,
+  duration_sec   INT          NOT NULL DEFAULT 0,
+  size_bytes     BIGINT       NOT NULL DEFAULT 0,
+  status         VARCHAR(16)  NOT NULL DEFAULT 'FAILED',
+  error_msg      VARCHAR(500) NOT NULL DEFAULT '',
+  created_at     TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  updated_at     TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  deleted        SMALLINT     NOT NULL DEFAULT 0
+);
+CREATE UNIQUE INDEX IF NOT EXISTS uk_media_thumbnail_episode
+  ON media_thumbnail (episode_id);
+CREATE INDEX IF NOT EXISTS idx_media_thumbnail_drama
+  ON media_thumbnail (drama_id);
+COMMENT ON TABLE media_thumbnail IS '单集缩略图雪碧图与 VTT 时间轴';
+
 -- ============================================================
 -- 八、运营补充（PRD 08 平台运营后台 / 10 上线）
 -- ============================================================
@@ -858,7 +884,7 @@ BEGIN
     'wallet', 'product', 'orders', 'store_receipt', 'entitlement', 'refund_record',
     'reconcile_task', 'creator', 'creator_document', 'content_submission',
     'creator_stat_daily', 'creator_settlement',
-    'transcode_task', 'media_rendition',
+    'transcode_task', 'media_rendition', 'media_thumbnail',
     'ops_notice', 'ops_daily_stat'
   ]
   LOOP