build(deps): bump the ai-sdk group across 1 directory with 2 updates

Bumps the ai-sdk group with 2 updates in the / directory: [@ai-sdk/mcp](https://github.com/vercel/ai) and [ai](https://github.com/vercel/ai).


Updates `@ai-sdk/mcp` from 1.0.19 to 1.0.20
- [Release notes](https://github.com/vercel/ai/releases)
- [Changelog](https://github.com/vercel/ai/blob/main/CHANGELOG.md)
- [Commits](https://github.com/vercel/ai/compare/@ai-sdk/mcp@1.0.19...@ai-sdk/mcp@1.0.20)

Updates `ai` from 6.0.78 to 6.0.81
- [Release notes](https://github.com/vercel/ai/releases)
- [Changelog](https://github.com/vercel/ai/blob/main/CHANGELOG.md)
- [Commits](https://github.com/vercel/ai/compare/ai@6.0.78...ai@6.0.81)

---
updated-dependencies:
- dependency-name: "@ai-sdk/mcp"
  dependency-version: 1.0.20
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: ai-sdk
- dependency-name: ai
  dependency-version: 6.0.81
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: ai-sdk
...

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

Author: dependabot[bot]

packages/backend/package.json

@@ -110,11 +110,11 @@
     "typecheck": "pnpm run generate && tsc --noEmit"
   },
   "dependencies": {
-    "@ai-sdk/mcp": "^1.0.19",
+    "@ai-sdk/mcp": "^1.0.20",
     "@ai-sdk/openai-compatible": "^2.0.28",
     "@huggingface/gguf": "^0.3.3",
     "@huggingface/hub": "^2.9.0",
-    "ai": "^6.0.78",
+    "ai": "^6.0.81",
     "express": "^5.2.1",
     "express-openapi-validator": "^5.6.2",
     "isomorphic-git": "^1.36.3",