[IMPL] Reorganize documentation

[Doomsk]

Description

Current documentation is not well structured, with clear tabs and sections, to guide a new user through the language ecosystem. The expected outcome of this issue is to reorganize the whole documentation in a way that gives a clear path to users on:

• how to get started
• introduction
• language concepts
• examples
• how/where to reach out
• contributing & code of conduct
• blog posts

The documentation is using mkdocs material theme. Other options can be considered, as long as good reasons are given (easy of deploying updated documentation, easy of writing new content, easy of adding new features, easy of maintaining and debugging, good aesthetics). Check the docs/ folder on this very repository to see what features are enabled and its content.

Expected behavior

• Define and perform documentation reorganization (website tree structure, individual pages, and even text can be moved around).
• Defining the documentation engine and which features to include, remove, improve, and moving the content to the new engine (should it be a new one) or adapt content to the new features.
• The new documentation (with engine, organization, etc) must reflect (or be able to reflect) the new visual identity ([IMPL] Define icon, logo, color pallet, etc. for the project #94).
• The "where to reach out" section should mention the H-hat channel at the UnitaryFoundation Discord server.
• The contributing can mention H-hat's issues and repository's pages.

Note: documentation website visual identity is defined on issue #94; here it's only about the content.

[ahkatlio]

I have submitted a result. Please check.

[SecludedPerson700]

the color plett theme is not given

[Doomsk]

the color plett theme is not given

@SecludedPerson700 this is a documentation organization issue, not the new visual identity one.