build(deps): bump pydantic-ai-slim from 1.38.0 to 1.56.0

Bumps [pydantic-ai-slim](https://github.com/pydantic/pydantic-ai) from 1.38.0 to 1.56.0.
- [Release notes](https://github.com/pydantic/pydantic-ai/releases)
- [Changelog](https://github.com/pydantic/pydantic-ai/blob/main/docs/changelog.md)
- [Commits](pydantic/pydantic-ai@v1.38.0...v1.56.0)

---
updated-dependencies:
- dependency-name: pydantic-ai-slim
  dependency-version: 1.56.0
  dependency-type: indirect
...

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

Author: dependabot[bot]