Menu Navigation - Collapse All Option

Currently, it's hard for doc users to find some detailed subpages where the name potential is unknown. E.g. if I search the OS compatibility matrix, I would need to know that the site is placed under `Tutorials & How-tos > Operating System Manager > Compatibility Matrix`.

As every user maybe expect this information at another location, we should give the user an easier option to give them an overview about all existing content. For this, a "Collapse All" menu item Button could help to scan the items quicker, as I don't need to collapse every single item.

Another option would be to have an index page, where all content item's menu is displayed in a tree structure.

Start by reviewing the current documentation menu described in the issue and determine whether a "Collapse All" control or a tree-style index best addresses navigation. Done means users can quickly view or scan all existing documentation content without manually collapsing each menu section.

Written by the indexing model from the issue text.