feat: add multi-provider support (Komga + Stripstream Librarian)

- Introduce provider abstraction layer (IMediaProvider, KomgaProvider, StripstreamProvider)
- Add Stripstream Librarian as second media provider with full feature parity
- Migrate all pages and components from direct Komga services to provider factory
- Remove dead service code (BaseApiService, HomeService, LibraryService, SearchService, TestService)
- Fix library/series page-based pagination for both providers (Komga 0-indexed, Stripstream 1-indexed)
- Fix unread filter and search on library page for both providers
- Fix read progress display for Stripstream (reading_status mapping)
- Fix series read status (books_read_count) for Stripstream
- Add global search with series results for Stripstream (series_hits from Meilisearch)
- Fix thumbnail proxy to return 404 gracefully instead of JSON on upstream error
- Replace duration-based cache debug detection with x-nextjs-cache header

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

src/app/page.tsx

@@ -1,4 +1,4 @@
-import { HomeService } from "@/lib/services/home.service";
+import { getProvider } from "@/lib/providers/provider.factory";
 import { HomeContent } from "@/components/home/HomeContent";
 import { HomeClientWrapper } from "@/components/home/HomeClientWrapper";
 import { ErrorMessage } from "@/components/ui/ErrorMessage";
@@ -8,7 +8,10 @@ import { redirect } from "next/navigation";
 
 export default async function HomePage() {
   try {
-    const data = await HomeService.getHomeData();
+    const provider = await getProvider();
+    if (!provider) redirect("/settings");
+
+    const data = await provider.getHomeData();
 
     return (
       <HomeClientWrapper>
@@ -16,13 +19,14 @@ export default async function HomePage() {
       </HomeClientWrapper>
     );
   } catch (error) {
-    // Si la config Komga est manquante, rediriger vers les settings
-    if (error instanceof AppError && error.code === ERROR_CODES.KOMGA.MISSING_CONFIG) {
+    if (error instanceof AppError && (
+      error.code === ERROR_CODES.KOMGA.MISSING_CONFIG ||
+      error.code === ERROR_CODES.STRIPSTREAM.MISSING_CONFIG
+    )) {
       redirect("/settings");
     }
 
-    // Afficher une erreur pour les autres cas
-    const errorCode = error instanceof AppError ? error.code : ERROR_CODES.KOMGA.SERVER_UNREACHABLE;
+    const errorCode = error instanceof AppError ? error.code : ERROR_CODES.HOME.FETCH_ERROR;
 
     return (
       <main className="container mx-auto px-4 py-8">