Add a language comparison page

[sonnyp]

Similar to the "Extensions" window, we should have a "Languages" window with a comparison table and links.

Similar to https://developer.gnome.org/documentation/introduction/languages.html but with a bit more focus on Workbench and developer experience

This will have 2 objectives

1. Help newcomers decide which language to use in Workbench
2. Encourage language maintainers to implement features

Here is an example

	Formatter	Linter	Library demos	Support	Recommended for
JavaScript	Yes	Yes	100	100%	Beginners
Vala	No	Yes	90	80%	Intermediate
Rust	Yes	No	90	80%	Intermediate
Python	No	No	0	50%	Beginners

Support would refer to UX, APIs and features, for example

• Allow using actions in the external preview #110
• Implement workbench.preview for Vala #125
• Support root object updates #120
• Improve first time Rust experience #630
• workbench.build

Note that these aren't Vala specific anymore.

[sonnyp]

Design wise we should have a little description for each language and an intro that says "Use what you are familiar with".

[sonnyp]

@bragefuglseth would you be interested in designing something like this?

[bragefuglseth]

Yeah! I think this should be in the already existing Extensions window, though, below the list of installed extensions. Seems like this is the place where it would be most relevant.

[sonnyp]

If you can find a way to merge both dialogs that's not confusing - I'm happy to :)

Remembers the Extensions window is currently used for "user attempts to do something they don't have the sdk for".

For the Languages window I had in mind to make it accessible via an info button here

and from the Library window "About Languages" or something.

But yeah there is a lot of overlap.

[gregorni]

I feel like there should also be links to the language API documentation.