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/types/stripstream.ts

@@ -0,0 +1,105 @@
+// Types natifs de l'API Stripstream Librarian
+
+export interface StripstreamBookItem {
+  id: string;
+  library_id: string;
+  kind: string;
+  title: string;
+  updated_at: string;
+  reading_status: "unread" | "reading" | "read";
+  author?: string | null;
+  language?: string | null;
+  page_count?: number | null;
+  reading_current_page?: number | null;
+  reading_last_read_at?: string | null;
+  series?: string | null;
+  thumbnail_url?: string | null;
+  volume?: number | null;
+}
+
+export interface StripstreamBookDetails {
+  id: string;
+  library_id: string;
+  kind: string;
+  title: string;
+  reading_status: "unread" | "reading" | "read";
+  author?: string | null;
+  file_format?: string | null;
+  file_parse_status?: string | null;
+  file_path?: string | null;
+  language?: string | null;
+  page_count?: number | null;
+  reading_current_page?: number | null;
+  reading_last_read_at?: string | null;
+  series?: string | null;
+  thumbnail_url?: string | null;
+  volume?: number | null;
+}
+
+export interface StripstreamBooksPage {
+  items: StripstreamBookItem[];
+  total: number;
+  page: number;
+  limit: number;
+}
+
+export interface StripstreamSeriesItem {
+  name: string;
+  book_count: number;
+  books_read_count: number;
+  first_book_id: string;
+}
+
+export interface StripstreamSeriesPage {
+  items: StripstreamSeriesItem[];
+  total: number;
+  page: number;
+  limit: number;
+}
+
+export interface StripstreamLibraryResponse {
+  id: string;
+  name: string;
+  root_path: string;
+  enabled: boolean;
+  book_count: number;
+  monitor_enabled: boolean;
+  scan_mode: string;
+  watcher_enabled: boolean;
+  next_scan_at?: string | null;
+}
+
+export interface StripstreamReadingProgressResponse {
+  status: "unread" | "reading" | "read";
+  current_page?: number | null;
+  last_read_at?: string | null;
+}
+
+export interface StripstreamUpdateReadingProgressRequest {
+  status: "unread" | "reading" | "read";
+  current_page?: number | null;
+}
+
+export interface StripstreamSearchResponse {
+  hits: StripstreamSearchHit[];
+  series_hits: StripstreamSeriesHit[];
+  estimated_total_hits?: number | null;
+  processing_time_ms?: number | null;
+}
+
+export interface StripstreamSearchHit {
+  id: string;
+  title: string;
+  series?: string | null;
+  library_id: string;
+  thumbnail_url?: string | null;
+  volume?: number | null;
+}
+
+export interface StripstreamSeriesHit {
+  name: string;
+  book_count: number;
+  books_read_count: number;
+  first_book_id: string;
+  library_id: string;
+}