Project settings tooltips improvement

[ZX-WT]

Operating system or device, Godot version, GPU Model and driver (if graphics related):
any godot version

Issue description:
I would like to ask whether the tooltips in project settings can be modified or not. I would like to add some simple description for the properties. If not, I may carry this discussion to the godot documentation and try to create a page about the settings.

[NathanLovato]

There's an issue up to create a reference in the docs, and help would be much welcome! godotengine/godot-docs#395
It seems there's no system in place for in-editor tooltips. If we build the reference for the online manual though, we'll have the content ready to add back to the editor when someone can work on this.

[NathanLovato]

The files aren't 100% up to date but pwab shared his project and editor settings templates

https://gist.github.com/pwab/78672798589591c37da4f49d3a08bc6c
https://gist.github.com/pwab/e6497658cd3021e725611e2fc30335da

I'd probably be best to have a tool similar to the doctool (or make it part of doctool) to re-generate the list if it changes

[DevinPentecost]

I briefly looked through the C++ code and it looks like most settings are defined and referenced directly by string (example). This seems like any changes to one would require the string reference to be updated in multiple places. Should there be a class that defines the settings and their paths/types/defaults/descriptions so that it can be referenced? I'm not an expert at C++ so forgive me if this is an antipattern of some sort.

I tried perusing the codebase to investigate adding the tooltips but I'm having a hard time finding where to start. Any ideas?

[vnen]

Related to #13370 (maybe both can be implemented together).

[vnen]

@DevinPentecost this should use a tool similar to doctool, writing/reading a XML file for the tooltips based on the full setting name. This way we can use the same source to make the documentation page and have tooltips in-editor.

Then the Project Settings dialog would read this file and add the tooltip accordingly. Same applies to the Editor Settings dialog.

For the import panel I mentioned in #13370, this would be a bit more complicated and I understand if it's left for later.

[Calinou]

As many of the project settings may have a long description, it could be a good idea to display tooltips at the bottom of the Project Settings window (in a RichTextLabel node or similar), rather than in a floating tooltip (which may have to span over several lines, and will disappear as soon as you move the mouse).

[DevinPentecost]

I was thinking it might be best to have two descriptions - a 'brief' description that is appropriate for tooltips, and a full/rich description that could have markup and such applied to it.

@Calinou I agree that having the majority of the details presented at the bottom of the settings window, but I still think it would be pretty helpful to have something more useful in the tooltip than just the setting_name.

[ZX-WT]

can we say that c69de2b solves the issue?

[akien-mga]

Indeed.