Development documentation

[javierbrea]

Development documentation should be added to the website. It shouldn't consist only in the typical "How to contribute" guide explaining how to open a PR and a fast style guide, such as the one that the project currently has.
It should be complete enough to make easy to contribute in the code to anyone that may be interested. So, it should include chapters like:

• Installation
• Repo structure
• How to run unit tests
• How to run component tests
• Development tools, such as Nx, Pnpm, etc. Including versions to install, how to, etc.
• Code style guides to everything not covered by linters, and also chapter about how to run linters locally, how to configure IDEs properly, git hooks, etc.
• How to update documentation, including a style guide.
• Style guide for writing tests: Types of tests, schemas about how they work, etc.
• Style guide for writing documentation
• Branching model and release workflow description and schemas