Stylelint is a css linter: https://stylelint.io/
As part of this change we have added two javascript scripts:
```
pnpm lint:css
pnpm lint:css:fix
```
Look at `.vscode/settings.json.sample` and `.vscode/extensions.json` for
configuration in VSCode.
---------
Co-authored-by: Joffrey JAFFEUX <j.jaffeux@gmail.com>
* Move new/edit category modals to its own page
* Fix JS tests
* Minor fixes to new-category UI
* Add mobile toggle
* Use global pretender endpoint so plugins can benefit too
* Alignment fix
* Minor review fixes
* Styling refactor
* Move some SCSS out of the modal
