fix(scrape): 单集名不再覆盖整剧 original_name 修复合集被拆集 + 媒体库页新增单库修复重刮

- 根因: 单集刮削把 TMDB episode.Name 写入 original_name(应为整剧原名),
  导致同剧每集 original_name 不同, 合集分组键回退到标题时被拆成多集无法合并。
  移除该覆盖, 保留单集 overview/剧照/评分/时长回填(不影响合集键)。
- 新增 RepairAndRescrapeLibrary 服务方法 + POST /admin/libraries/:id/repair-rescrape
  路由 + 媒体库页「修复+重刮本库」按钮, 可按库单独触发修复(回填占位符外部 ID)并重刮,
  既修空 ID 又借重刮覆盖此前被单集名污染的 original_name。

web/src/api/tools.ts

@@ -104,4 +104,11 @@ export const toolsAPI = {
     api
       .post<{ status: string }>('/admin/media/repair-rescrape', {})
       .then((r) => r.data),
+
+  // repairAndRescrapeLibrary 触发「单库修复+重刮」：只对指定媒体库回填占位符
+  // 外部 ID 并重刮，不影响其它库。后端异步执行，进度通过 WS "scrape" topic 推送。
+  repairAndRescrapeLibrary: (libraryID: string) =>
+    api
+      .post<{ status: string }>(`/admin/libraries/${libraryID}/repair-rescrape`, {})
+      .then((r) => r.data),
 }

web/src/pages/LibraryPage.tsx

@@ -5,6 +5,7 @@ import toast from 'react-hot-toast'
 import { ArrowLeft, Play, Film, Database, FileText, Search, Sparkles, Trash2, Pencil } from 'lucide-react'
 
 import { libraryAPI } from '../api/library'
+import { toolsAPI } from '../api/tools'
 import { storageAPI, type CloudScanStatus } from '../api/storage_config'
 import { api } from '../api/client'
 import { recycleAPI } from '../api/recycle'
@@ -32,6 +33,7 @@ export function LibraryPage() {
   const [scanning, setScanning] = useState(false)
   const [scanProgress, setScanProgress] = useState('')
   const [scraping, setScraping] = useState(false)
+  const [repairing, setRepairing] = useState(false)
   const [seriesToolBusy, setSeriesToolBusy] = useState('')
   const [manualSeriesScrapeOpen, setManualSeriesScrapeOpen] = useState(false)
   const [seriesMetadataEditOpen, setSeriesMetadataEditOpen] = useState(false)
@@ -279,6 +281,16 @@ export function LibraryPage() {
     finally { setScraping(false) }
   }
 
+  const handleRepairRescrape = async () => {
+    if (repairing) return
+    setRepairing(true)
+    try {
+      await toolsAPI.repairAndRescrapeLibrary(id)
+      toast.success('本库修复+重刮已加入后台队列，进度可在任务中查看')
+    } catch { toast.error('修复+重刮启动失败') }
+    finally { setRepairing(false) }
+  }
+
   const runSeriesTool = async (key: string, label: string, action: (media: Media) => Promise<unknown>) => {
     if (selectedSeriesEpisodes.length === 0) return
     setSeriesToolBusy(key)
@@ -427,6 +439,7 @@ export function LibraryPage() {
           <div className="flex flex-wrap gap-2">
             <button onClick={handleScan} disabled={scanning} className="btn-outline">{scanning ? '扫描中…' : '立即扫描'}</button>
             <button onClick={handleScrape} disabled={scraping} className="btn-outline">{scraping ? '刮削中…' : '刮削元数据'}</button>
+            <button onClick={handleRepairRescrape} disabled={repairing} className="btn-outline" title="回填本库占位符外部 ID 并重刮，修正空 ID / 拆集问题">{repairing ? '修复中…' : '修复+重刮本库'}</button>
           </div>
         )}
       </div>