docs: Add internal docs

[validcube]

Every docs I have ever written

TODO

• Update word style
• Remove Docusaurus specific styling
• Remove some TODOs files from my internal internal docs
• Merge some docs together?

[oSumAtrIX]

There are several inconsistencies in the documentation:

• The structure of the documentation does not align with any other repositories.
• Some markdowns are in uppercase, some in lowercase, some are mixed, and some start with numbers or consist only of numbers.
• Folder names vary between lowercase and uppercase.
• There is a mix of plural and singular terms in multiple instances.

Overall, there is no clear structure. For example, why is there a separate folder for prebuilds when the API also includes prebuilds? What is the purpose of having "prebuilds" documentation in the first place? The naming scheme lacks clarity, and the level of detail in the documentation varies significantly. At times, code is included, while other sections are either general or very specific. Additionally, Docusaurus should not be used at this stage, as it is not utilized by any other documentation.

Fundamental issues like this are difficult to review in a PR. Ideally start with a GitHub issue, discuss how the docs should look like, and any other details, like language, structure, what to include, naming schemes, quirks, problems and what not, then realize in a PR