refactor: use ScannerHandler directly for library convenience routes

Previously, library routes used a generic NewHandler for convenience routes.
Now uses cfg.ScannerHandler directly for consistency with other scanner
endpoints and to ensure proper handler-specific middleware is applied.

internal/router/library.go

@@ -16,7 +16,7 @@ func registerLibraryRoutes(cfg *Config) {
 	protected := e.Group("/api", jwtMiddleware)
 
 	// Create handler for library-specific convenience routes
-	h := handlers.NewHandler(cfg.Queries, cfg.ConnManager, cfg.QueueProcessor)
+	h := cfg.ScannerHandler
 
 	// Public library types endpoint
 	e.GET("/api/libraries/types", cfg.LibraryHandler.GetLibraryTypes)