Phase 5-9: Matching-Engine, Podcast-Support, Web-Interface + Player

Backend:
- Matching-Orchestrator mit deutschen Serien-Patterns (drei ???, TKKG, ...)
- Vollständige MusicBrainz-Integration (Tracklist → Kapitel, Cover Art Archive)
- OpenLibrary + Google Books als Fallback-Quellen
- Auto-Accept (≥0.75) vs zu_prüfen (0.5-0.75) vs kein Match
- Manuelles Matching: GET /api/items/:id/match/search, POST apply
- RSS-Feed-Manager: feedparser, iTunes Search, periodisches Update
- APScheduler für Podcast-Feed-Updates (konfigurierbares Intervall)
- Podcast-Router: Feed-URL setzen, Episoden, Feed-Suche
- HLS: FFmpeg läuft als Background-Task, wartet auf ersten Segment
- main.py: APScheduler + neue Router eingebunden

Frontend (React + Vite + Tailwind + HLS.js):
- Login-Seite mit Fehlerbehandlung
- Library-Seite: Grid/Listen-Ansicht, Suche, Tag-Filter, Pagination, Scan
- BookCard: Cover, Fortschrittsbalken, zu_prüfen Badge, Quick-Play
- BookDetail: Metadaten, Matching-Panel, Kapitel-Liste, Lesezeichen
- AudioPlayer: HLS.js, Kapitel-Marker auf Fortschrittsbalken, Speed,
  Sleep-Timer, Lesezeichen, Keyboard-Shortcuts (Space/Arrows)
- MiniPlayer: persistent an Fußzeile, expandierbar
- PodcastDetail: Feed-URL, iTunes-Suche, Episoden-Liste
- Admin-Panel: Benutzer/Bibliotheken/Einstellungen verwalten
- App.tsx: React Router, Auth-Guard, Player-Overlay

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

frontend/src/api/libraries.ts

@@ -0,0 +1,21 @@
+import api from './client'
+
+export const getLibraries = () =>
+  api.get('/api/libraries').then((r) => r.data.libraries)
+
+export const getLibraryItems = (
+  libraryId: string,
+  params?: { page?: number; limit?: number; search?: string; sort?: string }
+) => api.get(`/api/libraries/${libraryId}/items`, { params }).then((r) => r.data)
+
+export const searchLibrary = (libraryId: string, q: string) =>
+  api.get(`/api/libraries/${libraryId}/search`, { params: { q } }).then((r) => r.data)
+
+export const scanLibrary = (libraryId: string) =>
+  api.post(`/api/libraries/${libraryId}/scan`).then((r) => r.data)
+
+export const createLibrary = (data: object) =>
+  api.post('/api/libraries', data).then((r) => r.data)
+
+export const deleteLibrary = (id: string) =>
+  api.delete(`/api/libraries/${id}`).then((r) => r.data)