chore(deps): bump the backend-production group

Bumps the backend-production group in /backend with 2 updates: [helmet](https://github.com/helmetjs/helmet) and [ws](https://github.com/websockets/ws).


Updates `helmet` from 8.1.0 to 8.2.0
- [Changelog](https://github.com/helmetjs/helmet/blob/main/CHANGELOG.md)
- [Commits](helmetjs/helmet@v8.1.0...v8.2.0)

Updates `ws` from 8.20.1 to 8.21.0
- [Release notes](https://github.com/websockets/ws/releases)
- [Commits](websockets/ws@8.20.1...8.21.0)

---
updated-dependencies:
- dependency-name: helmet
  dependency-version: 8.2.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: backend-production
- dependency-name: ws
  dependency-version: 8.21.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: backend-production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

backend/package-lock.json

@@ -31,14 +31,14 @@
     "express": "^5.2.1",
     "express-basic-auth": "^1.2.1",
     "express-rate-limit": "^8.5.2",
-    "helmet": "^8.1.0",
+    "helmet": "^8.2.0",
     "lowdb": "^7.0.1",
     "music-metadata": "^11.12.3",
     "node-cache": "^5.1.2",
     "sharp": "^0.34.5",
     "slsk-client": "^1.1.0",
     "uuid": "^14.0.0",
-    "ws": "^8.20.1"
+    "ws": "^8.21.0"
   },
   "devDependencies": {
     "nodemon": "^3.1.14"