Add interactive ebook search & selection

Introduce interactive ebook support: adds two API endpoints to search (interactive-search-ebook) and create/select ebook requests (select-ebook), plus server-side handlers to route Anna's Archive (direct) and indexer (torrent/NZB) downloads. Frontend: extend RequestActionsDropdown and InteractiveTorrentSearchModal to support an "ebook" search mode and selection flow, and add hooks (useInteractiveSearchEbook / useSelectEbook). Settings: add ebook_auto_grab_enabled with UI toggle and enforce disabling when no ebook sources are enabled; settings GET/PUT updated to persist the flag (default = true to preserve behavior). Documentation updated (scheduler, ebook-sidecar, settings pages) and ranking algorithm docs/tests extended to cover ebook-related normalization and matching cases. Includes logging and ranking integration for indexer results and normalization for Anna's Archive handling.

src/app/api/admin/settings/route.ts

@@ -139,6 +139,8 @@ export async function GET(request: NextRequest) {
         flaresolverrUrl: configMap.get('ebook_sidecar_flaresolverr_url') || '',
         // General settings
         preferredFormat: configMap.get('ebook_sidecar_preferred_format') || 'epub',
+        // Auto-grab: default true to preserve existing behavior
+        autoGrabEnabled: configMap.get('ebook_auto_grab_enabled') !== 'false',
       },
       general: {
         appName: configMap.get('app_name') || 'ReadMeABook',