Fix matching: add missing subtitle field, proper error logging, match-all endpoint

- MatchResult was missing subtitle field, causing AttributeError in
  _apply_match that silently killed every background match task
- Wrap _apply_match in try/except with exc_info logging so failures
  are visible in docker compose logs backend
- New POST /api/libraries/:id/match-all endpoint to trigger matching
  for all unlocked items (useful for items scanned before the fix)
- Admin UI: Match button per library next to the Scan button

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

backend/app/routers/libraries.py

@@ -219,3 +219,33 @@ async def scan_library(
     background_tasks.add_task(scan_library_task, library_id, job.id)
 
     return {"id": job.id, "type": "scan", "libraryId": library_id}
+
+
+@router.post("/{library_id}/match-all")
+async def match_all_items(
+    library_id: str,
+    background_tasks: BackgroundTasks,
+    admin: User = Depends(require_admin),
+    db: AsyncSession = Depends(get_db),
+):
+    """Startet Matching für alle nicht-gematchten Items der Library."""
+    result = await db.execute(select(Library).where(Library.id == library_id))
+    if not result.scalar_one_or_none():
+        raise HTTPException(status_code=404, detail="Library not found")
+
+    items_result = await db.execute(
+        select(LibraryItem).where(
+            LibraryItem.library_id == library_id,
+            LibraryItem.match_locked == False,
+        )
+    )
+    items = items_result.scalars().all()
+    item_ids = [i.id for i in items]
+
+    async def _run_all():
+        from ..services.matcher import match_audiobook
+        for iid in item_ids:
+            await match_audiobook(iid)
+
+    background_tasks.add_task(_run_all)
+    return {"queued": len(item_ids), "libraryId": library_id}

backend/app/services/matcher.py

@@ -233,12 +233,15 @@ async def match_audiobook(item_id: str):
                 logger.warning(f"{source_name} Fehler: {e}")
 
         if best and best_score >= UNCERTAIN_THRESHOLD:
-            await _apply_match(db, item, best, best_score)
-            logger.info(f"Match angewendet: '{item.title}' ← {best.source} ({best_score:.2f})")
+            try:
+                await _apply_match(db, item, best, best_score)
+                await db.commit()
+                logger.info(f"Match angewendet: '{item.title}' ← {best.source} ({best_score:.2f})")
+            except Exception as e:
+                logger.error(f"_apply_match fehlgeschlagen für '{title}': {e}", exc_info=True)
         else:
             logger.info(f"Kein Match für '{title}' (beste Konfidenz: {best_score:.2f})")
-
-        await db.commit()
+            await db.commit()
 
 
 async def search_for_item(title: str, author: str | None = None) -> list[dict]:

backend/app/services/matching/base.py

@@ -7,6 +7,7 @@ class MatchResult:
     source: str  # musicbrainz / open_library / google_books
     source_id: str
     title: str
+    subtitle: str | None = None
     author: str | None = None
     narrator: str | None = None
     description: str | None = None

frontend/src/api/libraries.ts

@@ -14,6 +14,9 @@ export const searchLibrary = (libraryId: string, q: string) =>
 export const scanLibrary = (libraryId: string) =>
   api.post(`/api/libraries/${libraryId}/scan`).then((r) => r.data)
 
+export const matchAllLibrary = (libraryId: string) =>
+  api.post(`/api/libraries/${libraryId}/match-all`).then((r) => r.data)
+
 export const createLibrary = (data: object) =>
   api.post('/api/libraries', data).then((r) => r.data)
 

frontend/src/pages/Admin.tsx

@@ -1,7 +1,7 @@
 import React, { useEffect, useState } from 'react'
-import { Users, Library, Settings, Trash2, Plus, RefreshCw, Loader2, Check, X, FolderOpen, Pencil } from 'lucide-react'
+import { Users, Library, Settings, Trash2, Plus, RefreshCw, Loader2, Check, X, FolderOpen, Pencil, Sparkles } from 'lucide-react'
 import { getUsers, createUser, deleteUser, getSettings, updateSettings } from '../api/me'
-import { getLibraries, scanLibrary, createLibrary, updateLibrary, deleteLibrary } from '../api/libraries'
+import { getLibraries, scanLibrary, matchAllLibrary, createLibrary, updateLibrary, deleteLibrary } from '../api/libraries'
 import FileBrowser from '../components/common/FileBrowser'
 
 type Tab = 'users' | 'libraries' | 'settings'
@@ -214,6 +214,7 @@ function LibrariesPanel() {
   const [libraries, setLibraries] = useState<any[]>([])
   const [loading, setLoading] = useState(true)
   const [scanning, setScanning] = useState<string | null>(null)
+  const [matching, setMatching] = useState<string | null>(null)
   const [showCreate, setShowCreate] = useState(false)
   const [editingId, setEditingId] = useState<string | null>(null)
 
@@ -226,6 +227,12 @@ function LibrariesPanel() {
     setTimeout(() => setScanning(null), 5000)
   }
 
+  const handleMatchAll = async (id: string) => {
+    setMatching(id)
+    await matchAllLibrary(id).catch(() => {})
+    setTimeout(() => setMatching(null), 3000)
+  }
+
   const handleCreate = async (form: { name: string; path: string; mediaType: string; matchSources: string[] }) => {
     await createLibrary({
       name: form.name, folders: [{ fullPath: form.path }], media_type: form.mediaType,
@@ -293,6 +300,14 @@ function LibrariesPanel() {
                     <RefreshCw size={12} className={scanning === lib.id ? 'animate-spin' : ''} />
                     Scan
                   </button>
+                  {lib.mediaType !== 'podcast' && (
+                    <button onClick={() => handleMatchAll(lib.id)} disabled={matching === lib.id}
+                      title="Matching für alle Items starten"
+                      className="flex items-center gap-1 text-xs text-gray-400 hover:text-white bg-white/5 px-3 py-1.5 rounded-lg disabled:opacity-50 flex-shrink-0">
+                      <Sparkles size={12} className={matching === lib.id ? 'animate-pulse' : ''} />
+                      Match
+                    </button>
+                  )}
                   <button onClick={() => { setEditingId(lib.id); setShowCreate(false) }}
                     className="text-gray-500 hover:text-white p-1 flex-shrink-0">
                     <Pencil size={14} />