feat(video-pipeline): 增强参考图自动上传与视频生成重试机制

- 在 `init-manifest` 阶段添加输入文件清理日志和 WARNING 提示
- `getReferences` 改为异步并自动将本地参考图上传至 OSS，减少手动操作
- `phase-videos` 支持 `pending`/`failed` 状态 item 的自动重试，自动清理旧视频引用
- 优化 `phase-assemble` 中字幕与配音开关的逻辑，根据实际内容动态判断

.claude/skills/video-from-script/scripts/lib/phase-assemble.js

@@ -23,13 +23,17 @@ async function phaseAssemble(manifest, manifestPath, options) {
     }
   }
 
+  // 检测是否有配音和字幕
+  const hasAudio = manifest.items.some(it => it.audio)
+  const hasSubtitles = manifest.items.some(it => it.script && it.script.trim() && it.script !== '[无配音]')
+
   const assembleArgs = {
     input: dir,
     manifest: manifestPath,
     mode,
     format: manifest.format || accountConfig.defaultFormat || '9:16',
-    subtitles: 'true',
-    voiceover: manifest.items.some(it => it.audio) ? 'true' : 'false',
+    subtitles: hasSubtitles ? 'true' : 'false',
+    voiceover: hasAudio ? 'true' : 'false',
     animation: capcutConfig.animation || '渐显+放大',
   }
 
@@ -37,7 +41,7 @@ async function phaseAssemble(manifest, manifestPath, options) {
   if (capcutConfig.effects) assembleArgs.effects = capcutConfig.effects.join(',')
   if (capcutConfig.filter) assembleArgs.filter = capcutConfig.filter
 
-  log('assemble', `模式: ${mode}, 字幕: true, 配音: ${assembleArgs.voiceover}, 动画: ${assembleArgs.animation}`)
+  log('assemble', `模式: ${mode}, 字幕: ${assembleArgs.subtitles}, 配音: ${assembleArgs.voiceover}, 动画: ${assembleArgs.animation}`)
 
   try {
     const { assemble } = require('../capcut_assemble')