Refactor indexer management and improve search logic

Refactors admin settings to use a new IndexersTab and card-based indexer management UI, supporting category selection and improved configuration. Updates backend and API routes to handle indexer categories, propagate ASIN for better search scoring, and group indexers by categories to optimize Prowlarr searches. Enhances documentation to clarify non-terminal request matching and auto-completion behavior. Adds new reusable components for indexer management and category selection.

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

@@ -17,6 +17,7 @@ interface SavedIndexerConfig {
   priority: number;
   seedingTimeMinutes: number;
   rssEnabled?: boolean;
+  categories?: number[]; // Array of category IDs (default: [3030] for audiobooks)
 }
 
 /**
@@ -48,16 +49,19 @@ export async function GET(request: NextRequest) {
 
         const indexersWithConfig = indexers.map((indexer: any) => {
           const saved = savedIndexersMap.get(indexer.id);
+          const isAdded = !!saved;
 
           return {
             id: indexer.id,
             name: indexer.name,
             protocol: indexer.protocol,
             privacy: indexer.privacy,
-            enabled: !!saved, // Enabled if in saved list
+            enabled: isAdded, // Enabled if in saved list
+            isAdded, // Explicit flag for UI (new card-based interface)
             priority: saved?.priority || 10,
             seedingTimeMinutes: saved?.seedingTimeMinutes ?? 0,
             rssEnabled: saved?.rssEnabled ?? false,
+            categories: saved?.categories || [3030], // Default to audiobooks category
             supportsRss: indexer.capabilities?.supportsRss !== false, // Default to true if not specified
           };
         });
@@ -101,6 +105,7 @@ export async function PUT(request: NextRequest) {
             priority: indexer.priority,
             seedingTimeMinutes: indexer.seedingTimeMinutes,
             rssEnabled: indexer.rssEnabled || false,
+            categories: indexer.categories || [3030], // Default to audiobooks if not specified
           }));
 
         // Save to configuration (matches wizard format)