[Feature] Aliases for a better multi-language UX

[mcallegari]

We have setup a git-synced website for our documentation similar to the Grav docs: https://docs.qlcplus.org/v4

However, we don't have doc versions, but doc languages with a selector to switch among them.
Right now it is possible to define languages with suffixes that must be part of the filename to be recognized. (see screenshot)
Example: chapter.md -> chapter.de.md -> chapter.fr.md

What is missing and would greatly improve the user experience are "Language aliases"
The UI should have an additional field where we can enter an alias that is the actual string that will be displayed by the selector.
For example:
Selector Label: Deutsch
Language Suffix: de
Fallback Languages: en

In our case we would even have combinations of software versions + language (v4, v4_de, v4_fr, v5_fr, v5_it)
The best and most effective user experience would be to present "Version 4 English", "Version 5 Français", etc

Thank you in advance for considering this feature request!
And thank you for a great product like Grav! 🙏