Ruff lints the whole repo

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Describe the bug

Currently, Ruff lints all the files in the repo, which can be inefficient.

To Reproduce
Steps to reproduce the behavior:

1. Open a PR and take a look at the Ruff check details.

Expected behavior
Lint only the modified Python files.

Additional context
Proposed update to file .github/workflows/linters.yaml

- name: Check code style
      run: |
        . venv/bin/activate
        if [ "$GITHUB_EVENT_NAME" = "pull_request" ]; then
          git fetch origin ${{ github.base_ref }}
          CHANGED_FILES=$(git diff --name-only origin/${{ github.base_ref }}...${{ github.sha }} -- '*.py')
        else
          CHANGED_FILES=$(git diff --name-only HEAD^ -- '*.py')
        fi
        if [ -n "$CHANGED_FILES" ]; then
          python -m ruff format --check $CHANGED_FILES
          python -m ruff check $CHANGED_FILES
        fi

Start with .github/workflows/linters.yaml and inspect the existing Check code style step, then open a pull request to verify which files Ruff currently checks. Update the workflow so the Ruff format and lint commands receive only modified Python files, and confirm the check skips cleanly when no Python files changed.