archive mode does not support type aliases

Actual behavior

type MyThing = string

hits can't yet turn ... into a model.Type

Expected behavior

It should mock the interface

To Reproduce

type MyThing = string, then add it to an interface that's mocked in archive mode (think Bazel)

Additional Information

HEAD of everything.

Handling this is implemented in package_mode.go, but not in archive.go. The code at https://github.com/uber-go/mock/blob/main/mockgen/model/model_gotypes.go#L77 handles types.Named but not types.Alias. Should it do both?

diff --git a/mockgen/model/model_gotypes.go b/mockgen/model/model_gotypes.go
index 4596c3d..2703c9b 100644
--- a/mockgen/model/model_gotypes.go
+++ b/mockgen/model/model_gotypes.go
@@ -85,6 +85,17 @@ func typeFromGoTypesType(t types.Type) (Type, error) {
                }, nil
        }

+       if t, ok := t.(*types.Alias); ok {
+               tn := t.Obj()
+               if tn.Pkg() == nil {
+                       return PredeclaredType(tn.Name()), nil
+               }
+               return &NamedType{
+                       Package: tn.Pkg().Path(),
+                       Type:    tn.Name(),
+               }, nil
+       }
+
        // only unnamed or predeclared types after here

        // Lots of types have element types. Let's do the parsing and error checking for all of them.

Start with mockgen/model/model_gotypes.go, especially typeFromGoTypesType, and compare the existing handling there with archive.go and package_mode.go. Reproduce the type alias in an interface mocked in archive mode, then verify that archive mode accepts it and generates the mock instead of reporting that it cannot convert the type.