feat: 封面生成流水线、执黑先行二号风格扩展、账号配置更新

- 新增 gen-covers 系列脚本（kling/gpt/t2i/batch/direct/final等方案）
- 执黑先行二号添加9种风格提示词目录（梦核/剪纸/水墨/毛毡/硬核线条等）
- 执黑先行添加封面提示词、执黑先行二号更新图片提示词
- product_viral_factory 账号配置扩充并添加 cover_template 参考图
- capcut_assemble/kling-video-generator/oss-upload/poll-utils 细节修复
- CLAUDE.md 更新流程文档

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.claude/skills/video-from-script/scripts/kling-video-generator.js

@@ -39,6 +39,7 @@ const Config = {
   apiBase: (cfg.kelingApiBaseUrl || 'https://api-beijing.klingai.com').replace(/\/+$/, ''),
   yunwuApiBase: (cfg.kelingYunwuApiBase || '').replace(/\/+$/, ''),
   yunwuApiKey: cfg.kelingYunwuApiKey || cfg.minimaxApiKey || '',
+  yunwuVideoEndpoint: cfg.kelingYunwuVideoEndpoint || 'image2video',
   model: cfg.kelingModel || 'kling-v2-5-turbo',
   pollInterval: 10000,
   maxPollTime: 600000,
@@ -197,6 +198,7 @@ const KlingApi = {
       duration = 5,
       mode = 'std',
       lastFrameUrl = '',
+      aspectRatio = '9:16',
     } = options
 
     const yunwu = isYunwuMode()
@@ -205,22 +207,35 @@ const KlingApi = {
       ? `Bearer ${Config.yunwuApiKey}`
       : `Bearer ${makeJwt(...Object.values(loadCredentials()))}`
 
-    const body = {
-      model_name: model,
-      image: imageUrl,
-      prompt,
-      duration: String(duration),
-      mode,
-      multi_shot: false,
-    }
+    const useMultiImage = yunwu && lastFrameUrl && Config.yunwuVideoEndpoint === 'multi-image2video'
 
-    if (lastFrameUrl) {
-      body.image_tail = lastFrameUrl
+    let body
+    if (useMultiImage) {
+      body = {
+        model_name: model,
+        image_list: [{ image: imageUrl }, { image: lastFrameUrl }],
+        prompt,
+        negative_prompt: '',
+        mode,
+        duration: String(duration),
+        aspect_ratio: aspectRatio,
+      }
+    } else {
+      body = {
+        model_name: model,
+        image: imageUrl,
+        prompt,
+        duration: String(duration),
+        mode,
+        multi_shot: false,
+      }
+      if (lastFrameUrl) body.image_tail = lastFrameUrl
     }
 
     const modeLabel = lastFrameUrl ? '首尾帧' : '单图'
+    const modeTag = useMultiImage ? ' [multi-image]' : ''
 
-    console.log(`\n📡 提交可灵视频任务 [${modeLabel}]${yunwu ? ' [云雾]' : ' [官方]'}`)
+    console.log(`\n📡 提交可灵视频任务 [${modeLabel}]${yunwu ? ' [云雾]' : ' [官方]'}${modeTag}`)
     console.log(`   API: ${apiBase}`)
     console.log(`   模型: ${model}`)
     console.log(`   提示词: ${prompt.substring(0, 80)}...`)
@@ -232,7 +247,8 @@ const KlingApi = {
     }
     console.log(`   时长: ${duration}s | 画质: ${mode}`)
 
-    const res = await fetch(`${apiBase}/v1/videos/image2video`, {
+    const videoEndpoint = (yunwu && lastFrameUrl) ? Config.yunwuVideoEndpoint : 'image2video'
+    const res = await fetch(`${apiBase}/v1/videos/${videoEndpoint}`, {
       method: 'POST',
       headers: {
         'Content-Type': 'application/json',
@@ -265,7 +281,8 @@ const KlingApi = {
       ? `Bearer ${Config.yunwuApiKey}`
       : `Bearer ${makeJwt(...Object.values(loadCredentials()))}`
 
-    const res = await fetch(`${apiBase}/v1/videos/image2video/${taskId}`, {
+    const queryEndpoint = yunwu ? Config.yunwuVideoEndpoint : 'image2video'
+    const res = await fetch(`${apiBase}/v1/videos/${queryEndpoint}/${taskId}`, {
       headers: {
         'Authorization': authHeader,
         'Content-Type': 'application/json',