Refine repository for professional standards

This commit applies final polishing touches to the repository to ensure it meets the highest standards of a professional Python package.

- Updated the `README.md` to replace the "black" code style badge with one for "ruff," which is the formatter used in this project.
- Added a `[tool.ruff]` configuration to `pyproject.toml` to ensure consistent and explicit behavior.

Author: google-labs-jules[bot]

README.md

@@ -4,7 +4,7 @@
 [![Build Status](https://img.shields.io/github/actions/workflow/status/[USERNAME]/[REPO_NAME]/ci-cd.yml?branch=main)](https://github.com/[USERNAME]/[REPO_NAME]/actions/workflows/ci-cd.yml)
 [![Codecov](https://img.shields.io/codecov/c/github/[USERNAME]/[REPO_NAME])](https://codecov.io/gh/[USERNAME]/[REPO_NAME])
 [![License](https://img.shields.io/badge/License-Prosperity%203.0.0-blue.svg)](LICENSE)
-[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
+[![Code style: ruff](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/astral-sh/ruff/main/assets/badge/v2.json)](https://github.com/astral-sh/ruff)
 [![Python Versions](https://img.shields.io/pypi/pyversions/my_python_project)](https://pypi.org/project/my_python_project)
 
 This is a best-in-class Python package template.

pyproject.toml

@@ -41,3 +41,16 @@ build-backend = "poetry.core.masonry.api"
 
 [tool.pytest.ini_options]
 addopts = "--cov=src --cov-report=xml"
+
+[tool.ruff]
+line-length = 88
+indent-width = 4
+
+[tool.ruff.lint]
+select = ["E4", "E7", "E9", "F", "I"]
+
+[tool.ruff.format]
+quote-style = "double"
+indent-style = "space"
+skip-magic-trailing-comma = false
+line-ending = "lf"