/goal Improve the unit testing coverage of the codebase. You may want to run pytest --cov

-n4 to look at which files need coverage improvement. Update the threshold for CI when you've improved it as much as possible.

Completed in about 28 minutes of active work.

• Coverage improved from 93.54% to 99.54%.
• Statements: 99.82%; branches: 98.74%.
• CI threshold raised from 93% to 99% in pyproject.toml and .github/workflows/test.yml.
• Final suite: 1,927 passed, 6 skipped.
• git diff HEAD --check passes.
• Ruff remains unavailable locally (No module named ruff).
• Unrelated untracked directories were untouched.