x/tools/gopls: can show full type info instead of the name of type alias

[donnol]

I write some code like:

type Param struct {
        Name string
}

type A = Param 

func XXX(a A) {

}

when I put the cursor to the func param A, gopls show me type A = Param，how about show the origin info of Param instead?

I think it's very helpfull.

Thanks.

[danishprakash]

Making it configurable rather than the default would make more sense imho, have we had any discussion on this?