cmd/compile: internal compiler error: bad conversion to untyped: untyped bool

```
$ go version
go version go1.26-devel_45d6bc76af Fri Sep 26 00:30:55 2025 -0700 linux/amd64
```

```
package p

func f() *bool {
    var i int
    return new(i > 0)
}
```

```
$ go build crash.go

./crash.go:5:12: internal compiler error: bad conversion to untyped: untyped bool
```

cc @adonovan @golang/compiler 