pydantic-ai-middleware (Abandoned: Renamed to pydantic-ai-shields)

`pydantic-ai-middleware` was a library providing a simple middleware layer for Pydantic-AI agents, allowing for `before_run`/`after_run` hooks and other lifecycle management without imposing strict guardrails. The last version of this package was `0.2.4`. As of version `0.3.0`, the package was renamed to `pydantic-ai-shields`, and its core middleware functionality was integrated directly into `pydantic-ai` v1.71+.