Create project documentation improvements - how to use yarn

👉 Here you show how to start the server.

👉 But there are no examples of how to start a project with yarn.

👉 I am not a front-end expert and there is no npm/npx in the most popular drupal containers - docker4drupal

[shadcn]

there is no npm/npx in the most popular drupal containers - docker4drupal

I did not know that. I'll update the docs to add yarn commands. Thank you.