User guides

[pseusys]

Description

User guides is the new documentation partition containing article-style tutorials.

Checklist

• I have covered the code with tests
• I have added comments to my code to help others understand it
• I have updated the documentation to reflect the changes
• I have performed a self-review of the changes

[RLKRo]

I fixed some errors that I found in the commit.

[RLKRo]

Added a commit with minor changes: 6b63499.

EDIT: also, we have an option "header_links_before_dropdown": 7, due to which the about us section is getting moved to the more section.

I think we should either increase the limit or decrease it (so that, for example, development, community and about us would all be in the more section).

[pseusys]

Speaking of "header_links_before_dropdown": 7, let's increase it, it will collapse some sections if they don't fit into screen automatically.

[RLKRo]

BTW, here's how both options look like:

1. "header_links_before_dropdown": 8,:
   
2. "header_links_before_dropdown": 5,
   

[ruthenian8]

IMHO, still need to run a grammar check with ChatGPT