docs: adopt diataxis documentation principles for user-facing tutorials and how-to guides

## Summary

<img width="1920" height="1080" alt="Image" src="https://github.com/user-attachments/assets/1bbc3a40-988a-4f8b-9b2c-a94451c7ae6f" />

## Goals 
* Implement [diataxis](https://diataxis.fr/start-here/) documentation style into website tutorials / how-to guides