furnace.utilities: use a method based on where instead of vocab-path to ...

`{ my-app "index" } resolve-template-path` didn't use to work if `my-app` was in a path outside the `resource:` hieararchy. But now it does because I changed it to use the `where` word to find its filesystem path.
Maybe should do something like this instead:

```
first2 [ resolve-word-path ] [ append-path ] bi*
```

And then not have the ``but-last`` which is a bit of a code-smell.