chore(deps): update pydantic requirement in /api-server (#5)

Updates the requirements on [pydantic](https://github.com/pydantic/pydantic) to permit the latest version.
- [Release notes](https://github.com/pydantic/pydantic/releases)
- [Changelog](https://github.com/pydantic/pydantic/blob/main/HISTORY.md)
- [Commits](pydantic/pydantic@v2.0...v2.13.4)

---
updated-dependencies:
- dependency-name: pydantic
  dependency-version: 2.13.4
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

api-server/requirements.txt

@@ -1,4 +1,4 @@
 fastapi>=0.115.0
 uvicorn[standard]>=0.51.0
 httpx>=0.27.0
-pydantic>=2.0.0
+pydantic>=2.13.4