Add zizmor for GitHub Actions security linting

[adamtheturtle]

Add zizmor to dev dependencies and pre-commit config for GitHub Actions workflow security linting.

Changes

• Add zizmor==1.19.0 to dev dependencies in pyproject.toml
• Add zizmor pre-commit hook (runs on YAML files in .github directory)
• Add zizmor to ci.skip list (where applicable)

---

Note

Introduces GitHub Actions security linting via zizmor and wires it into local hooks.

• Adds zizmor==1.19.0 to dev dependencies in pyproject.toml
• New pre-commit hook: uv run --extra=dev zizmor .github (YAML, pre-commit, no filenames)
• Adds zizmor to ci.skip in .pre-commit-config.yaml to avoid running in pre-commit CI

^{Written by Cursor Bugbot for commit d0bdc3d. This will update automatically on new commits. Configure here.}