Add ESLint and Prettier with consistent formatting standards

- Add ESLint 9 and Prettier for consistent code formatting across docs repos
- Configure ESLint with TypeScript and Astro support
- Standardize lint and format commands across all repositories
- Upgrade to ESLint 9 flat config format (eslint.config.js)
- Update all ESLint and Prettier packages to latest versions
- Add CI checks to enforce formatting standards

Author: JonathanMatthey

packages/documentation/README.md

@@ -30,6 +30,18 @@ $ pnpm build:docs
 
 This command generates static content into the build directory and can be served using any static contents hosting service.
 
+- Format code and fix linting issues:
+
+```sh
+$ pnpm format
+```
+
+- Check formatting and linting:
+
+```sh
+$ pnpm lint
+```
+
 ## Editing Content
 
 Starlight looks for `.md` or `.mdx` files in the `src/content/docs/` directory. Each file is exposed as a route based on its file name. Due to the nature of how Starlight deals with content and their generated URLs, all docs content lives in `/src/content/docs/`. For example, the home page of the documentation lives within the `/src/content/docs/` folder and is rendered at rafiki.dev, not rafiki.dev/docs.
@@ -112,3 +124,12 @@ import Base from '../layouts/Base.astro';
 ```
 
 Refer to the Astro documentation on [pages](https://docs.astro.build/en/core-concepts/astro-pages/) for more detailed guidance.
+
+## Code Formatting
+
+This project uses [Prettier](https://prettier.io/) and [ESLint](https://eslint.org/) for code formatting and linting. Before submitting a pull request, please ensure your code is properly formatted:
+
+1. **Fix issues**: Run `pnpm format` to automatically fix formatting and linting issues
+2. **Check before pushing**: Run `pnpm lint` to verify everything passes (CI will also run this)
+
+ESLint is configured to work with TypeScript and Astro files. The configuration extends recommended rules from ESLint, TypeScript ESLint, and Astro ESLint plugins.