Fix download worker server entrypoint (#461)

* fix: update download worker path in package.json to reflect new directory structure

* fix: correct download worker path in package.json to align with updated directory structure

Author: clostao

apps/backend/package.json

@@ -14,7 +14,7 @@
     "start:fe:worker": "node dist/app/servers/frontendWorker.js",
     "start:download": "node dist/app/servers/download.js",
     "start:download:api": "node dist/app/apis/download.js",
-    "start:download:worker": "node dist/servers/downloadWorker.js",
+    "start:download:worker": "node dist/app/servers/downloadWorker.js",
     "lint": "eslint . "
   },
   "dependencies": {