Switch Python linting and formatting to Ruff

[KristopherKubicki]

Summary

• replace the black/flake8 setup with Ruff across pyproject settings, pre-commit hooks, the Makefile, and CI workflows
• refresh developer documentation and agent guidance to direct contributors to ruff format/ruff check
• regenerate the lock file and remove the obsolete .flake8 configuration so dependency metadata matches the new toolchain

Testing

• uv run ruff format --check . (fails: offline environment cannot download cached coverage wheel)

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Codex Task

[coderabbitai]

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✨ Finishing touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch codex/switch-from-flake-and-black-to-ruff

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[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Restore tabs in Makefile recipes for format/lint

The format and lint targets now use space indentation for their commands instead of tabs (uv run ruff… lines), so GNU Make treats those lines as malformed and exits with *** missing separator. Running make format or make lint currently fails before any Ruff tooling runs. Replacing the leading spaces with tabs (as still used by the test target below) restores working developer workflows.

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[Copilot]

Pull Request Overview

This PR modernizes the Python linting and formatting toolchain by replacing Black, Flake8, and isort with Ruff, consolidating three tools into one faster alternative. The migration updates all configuration files, developer documentation, CI workflows, and removes obsolete dependencies.

Key Changes:

• Replaces Black, Flake8, and isort with Ruff for Python code formatting and linting
• Updates pre-commit hooks to use ruff format and ruff check commands
• Refreshes developer documentation and agent guidance files to reference the new tooling

Reviewed Changes

Copilot reviewed 13 out of 14 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
uv.lock	Removes black, flake8, pycodestyle, pyflakes packages; retains mccabe and isort as transitive pylint dependencies
pyproject.toml	Removes [tool.black] and [tool.isort] sections; adds [tool.ruff.format] and [tool.ruff.lint] configuration; removes old tools from dev dependencies
.pre-commit-config.yaml	Replaces isort, black, and flake8 hooks with ruff-format and ruff check hooks
.flake8	Deletes obsolete Flake8 configuration file
Makefile	Updates format and lint targets to use ruff commands (contains critical indentation bug)
.github/workflows/release-packages.yml	Replaces flake8 lint steps with ruff format and check commands
README.md	Updates development instructions to reference ruff commands
docs/testing.md	Changes linting instructions from flake8 to ruff
docs/developer_guide.md	Updates test instructions to use ruff; removes stray command line
docs/ci_checks.md	Updates CI documentation to reflect Ruff usage
AGENTS.md	Updates agent guidance to reference ruff format and ruff check
app/AGENTS.md	Changes formatting reference from black to ruff format
tests/AGENTS.md	Updates pre-commit command reference to ruff check
app/routes.py	Changes noqa comment from flake8 to ruff format

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[Copilot]

Makefile recipes must be indented with tabs, not spaces. Lines 4, 5, 8, 11, 12, 13, and 25 use spaces, which will cause Make to fail with an error like "*** missing separator". Replace the space indentation with tabs for all recipe lines.

[Copilot]

Makefile recipe must be indented with a tab, not spaces. Replace the space indentation with a tab.

Suggested change

	prettier --write '*.yml'
	prettier --write '*.yml'

[Copilot]

Makefile recipes must be indented with tabs, not spaces. Replace the space indentation with tabs for all three recipe lines.

[github-actions]

Stale pull request message