Switch from black to ruff format

[MaxGhenis]

Summary

• Replace black and linecheck with ruff>=0.9.0 in dev dependencies
• Update Makefile and CI workflows (pr.yaml, push.yaml) to use ruff format instead of black and linecheck
• Remove [tool.black] section from pyproject.toml
• Reformat all files with ruff defaults (88 char line length)

Test plan

• ruff format --check . passes
• CI checks pass

Generated with Claude Code