chore(backend)(deps): bump yjs from 13.6.31 to 13.6.32 in /backend

Bumps [yjs](https://github.com/yjs/yjs) from 13.6.31 to 13.6.32.
- [Release notes](https://github.com/yjs/yjs/releases)
- [Commits](yjs/yjs@v13.6.31...v13.6.32)

---
updated-dependencies:
- dependency-name: yjs
  dependency-version: 13.6.32
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

backend/package-lock.json

@@ -61,7 +61,7 @@
     "ws": "^8.20.0",
     "yaml": "^2.0.0",
     "y-websocket": "^3.1.0",
-    "yjs": "^13.6.30",
+    "yjs": "^13.6.32",
     "graphql-ws": "^6.2.2",
     "zod": "^4.3.6"
   },