* feat: add Pydantic AI integration to CI, release pipeline, and docs
- Add test-pydantic-ai-integration job to CI (test.yml)
- Add build, publish, and artifact steps to release workflow (release.yml)
- Add hindsight-integrations/pydantic-ai to release.sh version bumping
- Add Pydantic AI documentation page (sdks/integrations/pydantic-ai.md)
- Add Pydantic AI entry to sidebar with icon
* docs: remove Requirements section from pydantic-ai integration page
