fix: supprime le layout shift des boutons qBittorrent au chargement

La config qBittorrent est maintenant récupérée côté serveur et passée
en prop au QbittorrentProvider, évitant le fetch client qui causait
l'apparition tardive des boutons de téléchargement.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/backoffice/app/components/QbittorrentDownloadButton.tsx

@@ -6,17 +6,19 @@ import { useTranslation } from "@/lib/i18n/context";
 
 const QbConfigContext = createContext(false);
 
-export function QbittorrentProvider({ children }: { children: ReactNode }) {
-  const [configured, setConfigured] = useState(false);
+export function QbittorrentProvider({ children, initialConfigured }: { children: ReactNode; initialConfigured?: boolean }) {
+  const [configured, setConfigured] = useState(initialConfigured ?? false);
 
   useEffect(() => {
+    // Skip client fetch if server already told us
+    if (initialConfigured !== undefined) return;
     fetch("/api/settings/qbittorrent")
       .then((r) => (r.ok ? r.json() : null))
       .then((data) => {
         setConfigured(!!(data && data.url && data.url.trim() && data.username && data.username.trim()));
       })
       .catch(() => setConfigured(false));
-  }, []);
+  }, [initialConfigured]);
 
   return <QbConfigContext.Provider value={configured}>{children}</QbConfigContext.Provider>;
 }