fix: SSR pour les providers cachés dans MetadataSearchModal

Les metadata providers sont récupérés côté serveur et les providers
sans API key sont passés en prop initialHiddenProviders, supprimant
le fetch client useEffect qui causait un layout shift.

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

apps/backoffice/app/components/MetadataSearchModal.tsx

@@ -27,6 +27,7 @@ interface MetadataSearchModalProps {
   seriesName: string;
   existingLink: ExternalMetadataLinkDto | null;
   initialMissing: MissingBooksDto | null;
+  initialHiddenProviders?: string[];
 }
 
 type ModalStep = "idle" | "searching" | "results" | "confirm" | "syncing" | "done" | "linked";
@@ -36,6 +37,7 @@ export function MetadataSearchModal({
   seriesName,
   existingLink,
   initialMissing,
+  initialHiddenProviders,
 }: MetadataSearchModalProps) {
   const { t } = useTranslation();
   const router = useRouter();
@@ -61,21 +63,7 @@ export function MetadataSearchModal({
   // Provider selector: empty string = library default
   const [searchProvider, setSearchProvider] = useState("");
   const [activeProvider, setActiveProvider] = useState("");
-  const [hiddenProviders, setHiddenProviders] = useState<Set<string>>(new Set());
-
-  // Fetch metadata provider settings to hide providers without required API keys
-  useEffect(() => {
-    fetch("/api/settings/metadata_providers")
-      .then((r) => r.ok ? r.json() : null)
-      .then((data) => {
-        if (!data) return;
-        const hidden = new Set<string>();
-        // ComicVine requires an API key
-        if (!data.comicvine?.api_key) hidden.add("comicvine");
-        setHiddenProviders(hidden);
-      })
-      .catch(() => {});
-  }, []);
+  const [hiddenProviders] = useState<Set<string>>(new Set(initialHiddenProviders ?? []));
 
   const visibleProviders = PROVIDERS.filter((p) => !hiddenProviders.has(p.value));