feat: improve type definitions and refactor API responses for better type safety

backend/src/routes/import.ts

@@ -1,10 +1,11 @@
 import { FastifyInstance } from 'fastify';
 import { runner } from '../jobs/importRunner';
 import { importDirectory } from '../services/importService';
+import type { ImportScanBody } from '../types';
 
 export default async function importRoutes(app: FastifyInstance) {
   app.post('/import/scan', async (request, reply) => {
-    const body = request.body as any;
+    const body = request.body as ImportScanBody;
 
     // Encolar el job en background
     setImmediate(() => {