types.ftl.go does not import ftl correctly

[matt2e]

Steps:

Add this verb to examples/go/time/time.go

//ftl:verb export
func OptionalResponse(ctx context.Context, rew TimeRequest) (ftl.Option[TimeResponse], error) {
	return ftl.None[TimeResponse](), fmt.Errorf("not implemented")
}

Add this verb to examples/go/echo/echo.go

//ftl:verb
func CallsOptionalResponse(ctx context.Context, client time.OptionalResponseClient) error {
	_, err := client(ctx, time.TimeRequest{})
	return err
}

This causes echo's types.ftl.go to be generated like this:

<...>
import (
	"context"
	ftltime "ftl/time"
	"github.com/block/ftl/common/reflection"
	"github.com/block/ftl/go-runtime/server"
)
<...>
		reflection.ProvideResourcesForVerb(
			CallsOptionalResponse,
			server.VerbClient[ftltime.OptionalResponseClient, ftltime.TimeRequest, ftl.Option[ftltime.TimeResponse]](),
		),
<...>

We get this build error:
Build failed: types.ftl.go:20:75: undefined: ftl because the verb client refers to ftl.Option but imports do not include ftl