Add Lidarr/Readarr backend support

- Add MUSIC and BOOK to MediaType enum
- Add permission flags for music/book requests
- Create Lidarr API adapter (artist/album search, add, remove)
- Create Readarr API adapter (book/author search, add, remove)
- Add Lidarr/Readarr settings interfaces and routes
- Add music and book API routes for search/detail
- Register all new routes in main router and settings router

server/lib/permissions.ts

@@ -29,6 +29,10 @@ export enum Permission {
   WATCHLIST_VIEW = 134217728,
   MANAGE_BLOCKLIST = 268435456,
   VIEW_BLOCKLIST = 1073741824,
+  REQUEST_MUSIC = 536870912,
+  AUTO_APPROVE_MUSIC = 2147483648,
+  REQUEST_BOOK = 4294967296,
+  AUTO_APPROVE_BOOK = 8589934592,
 }
 
 export interface PermissionCheckOptions {