Add ESLint configuration for consistent code quality

[Jerek0]

🧼 Add ESLint configuration for consistent code quality

This PR introduces a modern ESLint setup providing a consistent baseline for JavaScript, TypeScript, and Astro files. The configuration is lightweight and integrates smoothly with our existing tooling (Prettier, TypeScript, and lint-staged).

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🧠 Why?

This ESLint setup would work alongside Prettier to help us maintain a high-quality and reliable codebase.

While Prettier takes care of code formatting (spacing, line length, punctuation, etc.), ESLint focuses on code correctness, consistency, rigor, and safety. It adds another layer of confidence by:

• Preventing common bugs (e.g., unused variables, unreachable code, forgotten await)
• Enforcing safer patterns in TypeScript (e.g., discouraging use of any)
• Promoting consistent logic structures across contributors and teams
• Helping new developers onboard more easily by guiding them toward the expected practices

Together, Prettier and ESLint ensure our code is not only clean to look at—but also clean to run and maintain.

Note

This setup is inspired from one of our projects (Scout) and our pleasant experience with it.

🔧 What's included

• ✅ ESLint with official @eslint/js recommendations
• ✅ TypeScript support via @typescript-eslint
• ✅ Compatibility with Prettier using eslint-config-prettier
• ✅ Astro support via eslint-plugin-astro
• ✅ Linting is automatically run on staged files via lint-staged and simple-git-hooks

⚙️ How it works

• ESLint is configured in eslint.config.js using the new flat config format
• On pre-commit, the following happens automatically thanks to simple-git-hooks and lint-staged:
  • Prettier runs on all staged files (*) — as usual
  • ESLint runs on any staged .js, .ts, .jsx, .tsx, or .astro files and auto-fixes where possible
• This ensures that common issues are caught and fixed before they reach a commit

📁 Default ignores

The config ignores the following paths by default:

• .astro/ (Astro build artifacts)
• dist/ (build output)
• node_modules/

💬 Feedback welcome

💡 This setup is designed to be helpful without being intrusive. If you run into issues or have suggestions (e.g., rules to add or remove, formatting conflicts), feel free to open a discussion or contribute directly.

Let’s keep our code clean, consistent, and a little easier to love.

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Warning

This PR doesn't fix errors found by ESLint on the whole project. Since this PR only allows to run the linter on staged files, I chose to ignore those for the moment. Once merged, one should — probably me — create another PR to fix all the issues on the repo.

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Name	Status	Preview	Updated (UTC)
astro-boilerplate	✅ Ready (Inspect)	Visit Preview	Jul 3, 2025 5:53pm

[devenini]

Possible to convert eslint.config.js to TypeScript (.ts) so it’s consistent with the other JavaScript files in the repo?