Bump undici from 7.25.0 to 7.28.0

Bumps [undici](https://github.com/nodejs/undici) from 7.25.0 to 7.28.0.
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v7.25.0...v7.28.0)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 7.28.0
  dependency-type: direct:production
...

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

Author: dependabot[bot]

packages/core/package.json

@@ -98,7 +98,7 @@
     "pg": "^8.18.0",
     "pgvector": "^0.2.0",
     "tsx": "^4.21.0",
-    "undici": "^7.24.5",
+    "undici": "^7.28.0",
     "viem": "^2.48.11",
     "zod": "^4.3.6"
   },