Consider redrawing architecture diagram using Mermaid

[spbnick]

@gctucker said earlier:

ASCII art is cool, but for this static website there's also Mermaid which is easier on the eyes.

See this example: https://github.com/kernelci/kernelci-project/blame/main/kernelci.org/content/en/docs/architecture.md#L53 and how it's rendered: https://kernelci.org/docs/architecture/

Consider using that to make the architecture diagram nicer in doc/administrator_guide.md. One drawback, is that it becomes unreadable in the raw Markdown file, kinda defeating its original idea, but perhaps we could live with that for the sake of a prettier website.

[gctucker]

I guess an alternative would be to produce an image file e.g. SVG or PNG, so it could be seen independently from the website. At the moment, the documentation is more tailored for the website than standalone Markdown files to read in a different context.

[octonawish-akcodes]

I want to work on this