Documentation: Move documentation from GitHub Wiki to an indexable platform

[egeakman]

• GitHub wikis are not indexed, meaning users cannot find our documentation through search engines. Instead, they must already know we have wikis. In contrast, Read the Docs is indexed and appears in search results.
• Read the Docs provides built-in statistics, and we can also integrate non-invasive analytics services like Plausible. Additionally, it offers multiple theme options, enhancing customization.
• Using reStructuredText with Sphinx enables nice features such as internal referencing, which would improve documentation structure and navigation. Markdown could be used as well. See this and this.
• Read the Docs allows broader contributions, unlike GitHub wikis, where only users with specific permissions can edit or suggest changes. Hosting documentation in the repository makes it accessible for pull requests.