`for: ` and `if: ` don't work together

```ftd
-- ftd.text: $x
if: { x == 'z' }
for: $x in $ts

-- string list ts:

-- string: x
-- string: y
-- string: z

-- end: ts
```

Throws the following error:

```
fastn-Error: path: /, PackageError { message: "failed to parse ParseError { message: \"Expected Record field `fifthtry.site/ui/dashboard#x`, found: `String`\", doc_id: \"lets-talk.fifthtry.site/ui/dashboard\", line_number: 13 }" }
```