Indicate calls to Deprecated functions

[fedorareis]

Is your feature request related to a problem? Please describe.
Visually indicate when a deprecated function is being used.

Describe the solution you'd like
Something similar to other editors (like GoLand) where strikethrough is put over the use of a deprecated function. It might be nice to allow users to customize how this is displayed, but I think starting with a strikethrough is a good starting point.

Describe alternatives you've considered
I don't think there are any good alternatives that make the use of deprecated functions obvious to the programmer.

Additional context
Doc comments support a Deprecated: section but there isn't an easy way to tell if something that has been deprecated is being used without reading the documentation or hovering over the function call.

[findleyr]

This looks a lot like https://go.dev/issue/40447.

I agree that we should add this. It is one of our most requested features.

[hyangah]

If you use staticcheck (that's this extension's default 3rd party linter run by "go.lintOnSave" feature, and you can also enable this in gopls by using "gopls": { "ui.diagnostic.staticcheck": true }), SA1019 check will report this as diagnostic.

We have some ideas to integrate this as a default diagnostic but let's discuss this in the golang/go#40447.