Improve the contribute to codesandbox-client experence.

🌈 Feature

First I apologize I keep update this issue tring to reflect what I am working on curantly better. I am not good at this and in programing in general.

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Improve the contribute to codesandbox-client experence.

• Add howto contribute to codesandbox in codesandbox document to codesandbox-client
• Currently the link in contribution with title How-to contribute to opensource project is broken.
• change the dockerfile to use FNM (why are we usinga spacific node version? or explain whywe are not.)
• the ide is way to big and shoud default to differnt view on mobile
• After opening I got 100% cpu usage ( i think you fix this)
• it run horrible on mobile.
• I made a list bellow of things that don't make sence I would like to have them documented.

Start with CONTRIBUTING.md and the broken “How-to contribute to opensource project” link, then inspect the Dockerfile references to the Node version. Separate the documentation, setup, and mobile IDE concerns before making changes; done should mean the contribution guidance works, the Node setup is explained or updated, and the agreed mobile behavior is documented or improved.