feat: add metadata provider filter to series page

- Add `metadata_provider` query param to series API endpoints (linked/unlinked/specific provider)
- Return `metadata_provider` field in series response
- Add metadata filter dropdown on series page with all provider options
- Show small provider icon badge on linked series cards
- LiveSearchForm now wraps filters on two rows when needed

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

apps/backoffice/lib/api.ts

@@ -123,6 +123,7 @@ export type SeriesDto = {
   library_id: string;
   series_status: string | null;
   missing_count: number | null;
+  metadata_provider: string | null;
 };
 
 export function config() {
@@ -322,6 +323,7 @@ export async function fetchAllSeries(
   sort?: string,
   seriesStatus?: string,
   hasMissing?: boolean,
+  metadataProvider?: string,
 ): Promise<SeriesPageDto> {
   const params = new URLSearchParams();
   if (libraryId) params.set("library_id", libraryId);
@@ -330,6 +332,7 @@ export async function fetchAllSeries(
   if (sort) params.set("sort", sort);
   if (seriesStatus) params.set("series_status", seriesStatus);
   if (hasMissing) params.set("has_missing", "true");
+  if (metadataProvider) params.set("metadata_provider", metadataProvider);
   params.set("page", page.toString());
   params.set("limit", limit.toString());
 

apps/backoffice/lib/i18n/en.ts

@@ -550,6 +550,12 @@ const en: Record<TranslationKey, string> = {
   // Series filters
   "seriesFilters.all": "All",
   "seriesFilters.missingBooks": "Missing books",
+
+  // Metadata filter
+  "series.metadata": "Metadata",
+  "series.metadataAll": "All",
+  "series.metadataLinked": "Linked",
+  "series.metadataUnlinked": "Not linked",
 };
 
 export default en;

apps/backoffice/lib/i18n/fr.ts

@@ -548,6 +548,12 @@ const fr = {
   // Series filters
   "seriesFilters.all": "Tous",
   "seriesFilters.missingBooks": "Livres manquants",
+
+  // Metadata filter
+  "series.metadata": "Métadonnées",
+  "series.metadataAll": "Toutes",
+  "series.metadataLinked": "Associée",
+  "series.metadataUnlinked": "Non associée",
 } as const;
 
 export type TranslationKey = keyof typeof fr;